Resolving dual-task interference: An fMRI study
Yuhong Jiang
Harvard University
Correspondence should be addressed to
Yuhong Jiang
Department of Psychology
Harvard University
33 Kirkland Street, Room 820
Cambridge, MA 02138
E-mail:yuhong@https://www.doczj.com/doc/2f1778207.html,
Phone:(617)-496-4486
Fax:(617)-495-3728(“Room 820”)
Acknowledgement. This research is supported by a Helen Hay Whitney Research Fellowship and a Milton Fund to Y.J, and a Human Frontiers Grant to Nancy Kanwisher. It is also supported in part by the National Center for Research Resources (P41RR14075) and the Mental Illness and Neuroscience Discovery (MIND) Institute. I thank Nancy Kanwisher for her intellectual generosity and Rebecca Saxe and Laura C. Wagner for comments.
Abstract
The human cognitive system is severely limited in the amount of information it can process simultaneously. When two tasks are presented within a short stimulus-onset-asynchrony (SOA), reaction time of each task, especially task 2, is dramatically delayed. Previous studies have shown that such delay is accompanied by increased activation in right inferior frontal gyrus (GFi). In this study, we address the role of right GFi in resolving dual-task interference at two different stages: allocation of perceptual attention and response selection. We scan 12 subjects using functional MRI while they conduct two tasks – shape discrimination in task 1 and color discrimination in task 2 –and vary the SOA between tasks as 100 ms or 1500 ms. The targets are located at the center or at the periphery. When both are at the center, they compete primarily for response selection. When both are at the periphery, they additionally compete for the allocation of perceptual attention. Results show that the right GFi and frontal operculum regions are significantly more active in the short SOA than the long SOA condition, but only when subjects attend to the periphery in both tasks. We conclude that the right lateral frontal regions are important for resolving dual-task interference at the perceptual attention stage.
Introduction
One of the most fascinating aspects of human cognition is our ineffectiveness in conducting two tasks at the same time. Despite frequent wishes to divide attention between two tasks – such as turning left in traffic while carrying out a coherent conversation – most of us choose to stop performing one task until the other is complete. But what prevents one from responding to the traffic light at the same time as choosing the next sentence to say? Research in cognitive psychology has provided extensive evidence that human attention is limited in at least two respects: perceptual attention and response selection (Jiang & Kanwisher, 2003a).
Perceptual attention is used primarily to select targets and filter out distractors when multiple objects are presented. It can be simultaneously directed to approximately four visual objects. For example, in multiple-object tracking, subjects first see 10 dots, a few of them blinked initially, and then all dots move randomly on the screen. Subjects’ability to track the previously blinked dots is severely impaired if more than 4 dots are to be tracked (Pylyshyn & Storm, 1988).
Response selection also poses a cognitive limitation. Pashler and colleagues propose that there is a central cognitive bottleneck, involved whenever a stimulus has to be mapped onto a response on the basis of an arbitrary rule, such as deciding to step on the brake when the traffic light turns red (Pashler, 1984, 1994). Mapping a stimulus to a response – a decision process – precedes the execution of motor responses. Thus, while we can press a key and say a word at the same time (Pashler, 1993), we cannot simultaneously decide which key to press on the basis of a shape and decide which word to say on the basis of a tone.
Response selection is not only different from motor execution, but also separate from the allocation of perceptual attention. This is revealed in that the central bottleneck cannot be divided between two response selection processes, but perceptual attention can be divided between a few perceptual objects. Thus, when people encounter a competition for response selection, they hold the second task in a queue; but when they encounter a competition for perceptual attention, they divide a proportion of perceptual attention to each object. Therefore, perceptual attention can be simultaneously divided between up to four perceptual objects (Luck and Vogel, 1997; Pylyshyn & Storm, 1988), but response selection can only be sequentially allocated to one task at a time (Pashler, 1989, 1991).
In this study, we use functional MRI to investigate how the brain resolves dual-task interference at the stage of perceptual attention and the stage of response selection. Competition at a third stage – the motor response stage – has been addressed by a separate study by Herath et al. (2001) and will be discussed later. We use the “overlapping task” design, adopted from behavioral studies on the central bottleneck (Welford, 1952; Pashler, 1984). In this design, two tasks are presented, separated by a variable stimulus-onset-asynchrony (SOA). When the SOA is short (e.g., 100 ms), the two tasks overlap in time and compete for perceptual attention and response selection. In this case, subjects have to perform task 1 AND task 2. As the SOA increases (e.g., to 1500 ms), the two tasks no longer overlap, so subjects only need to perform task 1 OR task 2. The difference between a short SOA condition (“AND”) and a long SOA condition (“OR”) reflects how the brain copes with overlapping stages of processing between two different tasks.
Several previous neuroimaging studies have studied the effect of dual-task processing (e.g., Adcock et al., 2000; Bunge et al., 2000; D’Esposito et al., 1995; Klingberg, 1998; Koechlin et al., 1999). These studies compare blocks of concurrent processing of two tasks (e.g., sentence comprehension and mental rotation) with blocks of single tasks alone. They observe increased activation in the dual-task condition in the dorsolateral prefrontal cortex and other regions. This suggests that additional central executive control is needed to resolve the dual-task interference. However, two design properties make these studies non-ideal for determining what goes on during overlapping processes. First, the dual-task condition uses a mixed-block design, which entails task-set switching between the two tasks (Allport & Wylie, 2000; Monsell & Driver, 2000). When a difference is found between a mixed-block and a single-task block, it may be attributed to either dual-task processing or task-set switching. Second, although the two tasks overlap in time in some studies, other studies have deliberately avoided overlapping processing. For example, in Klingberg’s (1998) study, the two tasks in the dual-task block are scheduled apart by 1 second to avoid a competition in motor output, so the dual-task blocks actually involve the processing of “task 1 OR task 2”. In D’Esposito et al., Adcock et al., and Bunge et al.’s studies, although the two tasks are presented inside the same time window, each trial of one or both tasks is extended for several seconds. This may allow subjects to sequentially perform the two tasks (cf Pashler, 1994). Thus, these studies have primarily examined the effect of maintaining two task sets and switching between them (“OR” versus single tasks; see also Dove et al., 2000; Kimberg et al., 2000; Konishi et al., 19998; MacDonald et al., 2000; Rushworth et al., 2002), and have not isolated the effect of overlapping task processing per se (“AND” versus “OR”).
Four other studies have investigated the effect of overlapping tasks. Herath et al. (2001) present two tasks separated by either a short SOA (200-300 ms) or a long SOA (1150-1350 ms). One task is a simple visual RT task, in which subjects press a key whenever an LCD is illuminated. The other task is a simple tactile RT task, in which the subjects press another key whenever they receive a tactile stimulation. The choice of two different input modalities minimizes competition for perceptual processing (Pashler, 1998), and the choice of two simple RT tasks minimizes competition for response selection (Pashler, 1994). Herath et al. find increased activation in the right inferior frontal gyrus (GFi) in the short SOA compared with the long SOA condition. They suggest that the activation result from a competition for the same motor effector.
Szameitat et al. (2002) and Schubert and Szameitat (2003) test the brain regions involved in tasks that overlap at a central stage. They use two choice-RT tasks that compete for the central bottleneck: a visual-motor and an auditory-motor task. Subjects are tested in a short SOA condition and blocks of single tasks. The short SOA condition show increased activation in right GFi compared with single tasks, suggesting that this region is involved not only in competition for the same motor effector (Herath et al., 2001), but also in competition for the central bottleneck. The interpretation of Szameitat et al’s and Schubert and Szameitat’s studies is limited, however, by the omission of a long SOA condition. As noted earlier, the difference between a short SOA condition and single task blocks includes two components: resolving dual-task interference and switching task sets. It is unclear whether the right GFi activation is produced by the need to switching task sets in the short SOA condition, by competition for the central bottleneck, or both. In fact, when a long SOA condition is added in a recent fMRI study (Jiang et al., in press), the difference between the short SOA and the long SOA condition
in the right GFi and other brain regions largely disappears, while the difference between the long SOA condition and single task blocks remains (Jiang et al., in press). This suggests that the right GFi may be more involved in task-set switching than in overlapping processing of response selection.
In this study we further investigate the role of the right GFi in resolving dual-task interference at two different stages: perceptual attention and response selection. We hypothesize that GFi is activated whenever two processes proceed simultaneously, but not when they occur sequentially. We further hypothesize that simultaneous processing occurs when two perceptual processes or when two motor processes are separated by a short SOA, but not when two response selection processes are separated by a short SOA. As a result, the GFi will increase its activation when two tasks compete for the allocation of perceptual attention or for motor processing (Herath et al., 2001), but not when they compete for response selection. This study focuses on perceptual attention and response selection.
We test subjects in three task combinations: when subjects attend to the center target in both tasks, when they attend to the center target in task 1 and to the peripheral target in task 2, and when they attend to the peripheral target in both tasks.
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On each display subjects are presented with one central target, one peripheral target, and seven peripheral distractors. The items are geometric shapes in task 1 (square or circle as the targets and triangles as the distractors) and colors in task 2 (red or green as the targets and mixed colors as the distractors). Subjects are told to attend
either to the central or to the peripheral targets and make responses to the target’s shape in task 1 and to the target’s color in task 2. Because the perception of a central target is easy, the competition involved in the center-center condition is primarily between the response selections of the two tasks. In the center-periphery condition, subjects have to shift attention from the center to the periphery. Finally, in the periphery-periphery condition the two tasks compete not only for response selection but also for spatial attention to the periphery. Thus, while response selection is the main competition in the center-center condition, perceptual attention is an additional source for competition in the periphery-periphery condition. Will the neural substrates involved in resolving these two kinds of interference be different?
Method
Participants: Twelve healthy adults between 18 and 32 years old were tested. They all had normal or contact-corrected normal visual acuity and normal color vision. Subjects participated in a 30 min practice before scanning.
Tasks: Ten subjects completed 6 sessions of fMRI scans; the other two subjects completed 2 sessions. Each session included 6 task blocks, composed of 3 task combinations and 2 SOAs. Each task block was preceded by a 14 second fixation and a 2 second instruction. The instruction informed subjects whether they should attend to the center or to the periphery. Each task block lasted 48 seconds and included 16 task pairs presented at 3 seconds / pair. Each display contained one central target, one periphery target, and 7 periphery distractors. The items in task 1 were geometric shapes. The distractors were triangles and the targets were square or circle. The items in task 2 were colored crosses. The distractors had mixed colors with one segment being red and the
other segment being green. The targets were pure colors of either red or green. The peripheral target was chosen randomly from 8 locations on an invisible circle (Radius = 3.3 degrees for task 1, and 3.0 degrees for task 2). Its identity could be the same or different from the central target. Figure 1 shows a sample display.
The instruction informed subjects to attend to (1) the central shape and the central color; (2) the central shape and the peripheral color; or (3) the peripheral shape and the peripheral color. Subjects were asked to press ‘1’ for a square and ‘2’ for a circle, using their left hand, and to press ‘3’ for red and ‘4’ for green, using their right hand. Attention was tested in different blocks.
Each trial started with the presentation of the first task display for 0.1 seconds. After an interval of zero or 1.4 s the second task display was presented for 0.1 seconds. The displays were presented briefly to discourage eye movements to the peripheral targets. Subjects were asked to respond as accurately and as quickly as possible to both tasks, within a time-window of 3 seconds.
FMRI design: Subjects were tested in the Martinos imaging center in Charlestown, MA, on Siemens 3.0 T research scanners. We first collected 128 saggital slices during the anatomical scans. During the functional scans 28 contiguous axial slices (4mm thick) were taken to cover the whole brain except the bottom half of the cerebellum (TR = 2s, TE=30ms, flip angle = 90 degrees). Each functional scan lasted 6 min 40 s, including 6 task blocks (48s each) and 7 fixation blocks (16s each). The first 6 fixation blocks (each preceding a task block) were composed of 14s of fixation and 2s of instruction. The order of the six task blocks was counter-balanced.
FMRI data analysis. Using SPM99, we first preprocessed each subject’s data, including motion correction, normalization to the MNI space, and spatial smoothing
with a Gausian kernel (FWHM = 5mm). Low frequency drifts were corrected in the analysis. Individual subjects’ data were analyzed to test for “all task > fixation” and the main effect of “short SOA > long SOA”. These contrast maps were then tested in a random-effect model for across subjects’ consistency. Because of the small number of subjects, a threshold of P < .001 (extended to 5 voxels) uncorrected for multiple comparisons was used. Finally, based on the “task > fixation” contrast, we defined 15 functional regions of interest (ROI) including the parietal cortex, frontal eye fields, lateral prefrontal cortex, basal ganglia, occipital cortex, and cerebellum, and tested the percent signal change (PSC) in each task condition.
Results
1.Behavioral results.
We calculated accuracy for all trials, RT for correct trials, and the correlation between task 1 and task 2’s RT. Table 1 shows the results.
Presenting the two tasks within 100ms of each other led to a dramatic increase in RT 1 of about 200ms and in RT2 of about 400ms. An ANOVA on attention (center-center, center-periphery, periphery-periphery) and SOA (short vs. long) revealed significant main effects of attention and SOA in RT1 and RT2, P’s < .0001. The interaction between attention and SOA was not significant for RT1, but was significant for RT2, P < .001. The SOA effect on RT2 was substantially larger when subjects attended to the peripheral targets (periphery-periphery, PRP = 491 ms) than when they attended to the central targets (center-center, PRP = 329 ms). This is consistent with the idea that the two tasks competed not only for response selection (which should be the same in all task combinations), but also for spatial attention when subjects attended to
the periphery. Further evidence that task 2 was waiting for the completion of task 1 came from the correlation data between RT1 and RT2. The correlation coefficients were about .30 when the SOA was long, but jumped to around .80 when the SOA was short.
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2.fMRI results
(1) The effect of SOA
A random-effects analysis on the main effect of SOA (short SOA > long SOA, averaged across different task combinations) revealed two regions that showed an increased activation in the short SOA condition. The right inferior frontal gyrus (area 9, [48 15 33], 6 voxels) and the right frontal operculum (area 47, [30 24 0], 11 voxels) were significantly more active during the short than the long SOA conditions (Figure 2).
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To find out whether these two frontal regions showed a significant SOA effect in all task combinations, we calculated the percent signal change (PSC) in two regions-of-interest (ROIs) centered on the above locations (radius = 6mm). This analysis showed that the SOA effect was primarily driven by a higher PSC for short than long SOA conditions when subjects attended to the periphery in both tasks. The SOA effect was significant in the periphery-periphery condition in both frontal regions (P < .05), but was not significant in the other two conditions (P > .15). The interaction between SOA
and attentional condition was significant in the frontal operculum (P < .05) and was marginally significant in the GFi (P < .08).
(2) Regions of interest analysis.
To find out whether we had missed any other brain regions involved in resolving the competition between two concurrent tasks, we used a regions-of-interest (ROI) approach to increase statistical power. We selected 15 additional brain regions that showed a significant effect of “task > fixation” (P < .001 uncorrected, random effects analysis). The ROIs were centered on the most significant voxel and included all task-related voxels (“task > Fixation”) within a spherical volume of 9mm of the peak voxel. Figure 3 shows task related activation and Table 2 shows the percent signal change above fixation in the 15 ROIs.
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All ROIs showed a significant main effect of attention, with higher PSC when subjects attended to the periphery (center-periphery and periphery-periphery) than when they attended to the center. Only one region – right anterior IPS, showed a significant main effect of SOA, with higher PSC during the short than the long SOA conditions. The SOA effect was significant in the center-periphery and periphery-periphery conditions, but was not significant in the center-center condition.
It is interesting that the behavioral interference effect associated with SOA (about 400ms) was numerically larger than that associated with allocating attention to the
periphery (about 140ms), yet many more brain regions were sensitive to spatial attention than to the competition induced by shortening the SOA.
Discussion
In this study we confirm that a significant behavioral interference is observed when subjects have to perform two tasks overlapping in time. The duration of response to both tasks is dramatically increased (by about 200 ms in task 1 and about 400 ms in task 2). The interference is larger when both targets are in the periphery than when they are at the center. This suggests that in addition to competing for response selection, the two tasks compete for perceptual attention in the periphery-periphery condition. Results show a significant increase in activation in the right lateral prefrontal regions when the two tasks are presented within a short SOA rather than a long SOA. This activation is primarily driven by the periphery-periphery condition, suggesting that the right GFi is important for resolving interference at the level of perceptual attention.
The greater sensitivity of the right GFi to competition for perceptual attention than to competition for response selection is consistent with the idea that these two types of interference are resolved differently. Unlikely response selection, perceptual attention is divisible and can be simultaneously allocated to two tasks (Pashler, 1989). On this account, subjects in the periphery-periphery, short SOA condition allocate perceptual attention to both targets simultaneously, although both tasks may be impaired because of the limited resources for perceptual attention. In contrast, when the two tasks compete mainly for response selection, as is the case in the center-center, short SOA condition, the interference is resolved primarily by holding task 2 in a queue. Because the working memory load produced by holding task 2 in a queue is minimum,
the short and the long SOA conditions are essentially processed similarly. That is, in both conditions the two response selection processes are dealt with sequentially.
At first glance, the emphasis on the role of right GFi in resolving perceptual interference appears to be inconsistent with previous functions attributed to this region. Many studies have shown, for example, that the right GFi is involved in suppressing a prepotent response and in making a response selection (e.g., Bunge et al., 2002; Jiang & Kanwisher, 2003a, b; Hazeltine et al., 2000; Passingham et al., 2000; Sohn et al., 2000; Rubia et al., 2003). Few studies have ascribed a role of perceptual attention to the right GFi (Duncan & Owen, 2000). How should we reconcile the present result with other findings?
The answer to this question lies in that the current study is specifically about resolving overlapping task processing, while the other studies have focused on a given stage of process in single tasks. That is, we compared a short SOA condition with a long SOA condition, while other studies compared the presence with the absence of a certain cognitive process, such as inhibition of prepotent response. When subjects conduct a single task, which requires them to select a target among distractors, and to map the target onto an appropriate response, the right GFi is involved both during perceptual attention and during response selection (Jiang & Kanwisher, 2003a, 2003b). The particular process tapped in the current study though, is not about how perceptual attention or response selection is conducted, but about how the brain deals with overlapping task processes. Our finding is that the right GFi appears to be highly sensitive to overlapping perceptual attention processes, and less so to overlapping response selections. This finding fits well with behavioral observations that perceptual attention can be divided between multiple objects, but response selection has to proceed
sequentially. That is, presenting two tasks simultaneously changes how perceptual attention is allocated, but it does not change how response selection is conducted. When the SOA is long, both perceptual attention and response selection are allocated sequentially, whereas when the SOA is short, perceptual attention is allocated simultaneously and response selection remains sequential. In addition to perceptual attention, motor processing can be conducted in parallel (Pashler, 1994): one can simultaneously press a key and say a word, for example. Reducing the SOA between two tasks also potentially changes motor processes from sequential allocation to simultaneous allocation. Consistent with this analysis, Herath et al. found that the right GFi is involved in resolving interference at the level of motor process.
To conclude, we found that the inferior frontal gyrus, frontal operculum, and anterior IPS of the right hemisphere increase their level of activation when two tasks overlap in time. This is observed particularly when both tasks compete for perceptual attention. We suggest that in addition to their roles in response selection and perceptual attention of single tasks, the right ventral prefrontal regions are involved when attention has to be simultaneously divided between two perceptual attention processes.
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Table 1. Behavioral data collected during scanning.
Attention Center-center Center-periphery Periphery-periphery SOA Short Long Interference Short Long Interference Short Long Interference Accuracy1.99.97-.02, n.s..94.92-0.03, n.s..92.940.02, n.s. Accuracy2.95.950, n.s..84.870.03, n.s..88.910.03 *
RT1 (ms)805570235 ***944647297 ***1025776186 ***
RT2 (ms)931602329 ***1193747445 ***1232741491 ***
r(RT1,RT2).85.35N/A.80.30N/A.80.24N/A
Difficulty Rating #4.73 3.86 D = 0.87,
n.s.
8.25 6.18 D = 2.07 **8.37 6.83 D = 2.46 **
1 was “very easy” and 10 was “very difficult”. * P < .05; ** P < .01; *** P < .001; n.s. non-significant; N/A not applicable.
---------------------------------------------------------------范文最新推荐------------------------------------------------------ 学校学生请假条格式【通用】 学生请假的理由有很多种，下面是小编精心整理的学校学生请假条格式，希望能给大家带来帮助! 学校学生请假条格式一 尊敬的______老师： 您好! 您的学生________因______________________需请假__________学时，望老师批准。 (请假日期：__________年_____月_____日至__________年_____月_____日) 请假人：______________ _____________________学院 _______________________(班级) 联系电话__________________________________ __________年_____月_____日 班主任：(签字)________________________________ 学办：(签字、盖章)________________________________ 学院签字：签字________________________________ 备注：请用整张信纸，按照以上格式黑笔书写，一式二份，三天以上学院领导签字。 学校学生请假条格式二 1 / 15
张老师： 今天，我因感冒发烧，不能到校上课，请假一天，请予批准! 请假人： 日期 学校学生请假条格式三 尊敬的老师： 您好! 我系XX年级XX几班的XX同学。我一直学习拉丁舞x年了。我报名了在X天xx地方举行的拉丁舞比赛。因为明天晚上要进行最后的彩排，后天上午9点比赛。因此会印象上课。在此深感抱歉，需要向老师(学校)请假，时间是明天下午到后天中午。 望老师(学校)予以支持和谅解，给予批准，在此为谢! XXX XX年XX月XX日 学校学生请假条格式四 由于运动会，我系院有以下运动员要参与训练，故不能参与XX月XX号至XX月XX号晚自习，请谅解! 参与训练名单如下： XX级XXX班：姓名学号 姓名学号 姓名学号 姓名学号
福州格致中学2014-2015学年第一学段 高一英语《必修一》模块考试 第二部分：英语知识运用 单项填空 从每题所给的A、B、C、D四个选项中，选出可以填入空白处的最佳答案，并在答题卡上将该选项涂黑。 21.In _______ distance is a tall tree which is said to have ______ history of over 500 years. A. the; a B. /; / C. a; a D. the; / 22.--- Look! The telephone is broken. Someone damaged it _______ purpose. --- That may be right. But perhaps it was broken ________ accident. A. on; on B. on; by C. by; by D. by; on 23.It might be very difficult to find _______ of the information. A. cause B. resource C. source D. course 24. Shall we go there by bus or by taxi? The ______ seems to be quicker. A. late B. latter C. later D. lately 25. After living in the United States for fifty years, he returned to the small town where he ______. A. brought up B. grew up C. gave up D. turned up 26. The engine of the ship was out of order and the bad weather ________ the helplessness of the crew(船员) at sea. A. added to B. added up to C. added up D. was added to 27. --- Daddy, I don’t want to go to Jimmy’s birthday. --- You had better go. ______ you make a promise, you have to keep it. A. Even B. Once C. Unless D. In case 28. --- Won’t you stay for lunch? --- No, thanks, I _______ my uncle at the airport at 10:30. A. met B. have met C. meet D. am meeting 29. ________ out for food, Some work in the nest as guards or workers. A. All the bees not go B. Both the bees don’t go C. Not all the bees go D. All the bees go 30. The old town has narrow streets and small houses _______ are built close to each other. A. they B. where C. what D. that 31. --- Don’t you know our town at all? --- No, It is the first time I _______ here. A. was B. am coming C. came D. have come 32. Can you make sure _____ the gold ring? A. where Alice had put B. where had Alice put C. where Alice has put D. where has Alice put 33. He decided to help the poor girl _______ were killed in the earthquake. A. which parents B. parents of them C. whose parents D. whom parents 34. The settlement is home to nearly to 1,000 people, many of _______ left their village homes for a better life in the city. A. whom B. which C. them D. who 35. ---We could invite John and Barbara to the Friday night party. --- Yes, _______ ? I’ll give them a call right now. A. why not B. what for C. why D. what 第二节完形填空（共20 小题；每小题一分，满分20分） 阅读下面短文，从短文后各题所给的四个选项（A,B,C,D）中选出可以填入相应空白处的最佳选项，并在答题卡上将该选项涂黑。 This little story I’m going to tell you happened when I was about 11 years old and I’II never forget it. I was at my friend Jenny’s __36__ after school one day, and we were doing (or not doing) homework.. __37__ I was there, Jenny’s mom came over to visit. I don’t remember her name__38__ what her face looked like. I just remember her hands, her voice and the__39__ she taught me. I can still see her hand __40__ for mine in our introduction. __41__ were so
春风拂面 每每想起老师，仿佛总有一股春风从面前拂过。它那样温暖，那样和煦，像润物无声的细雨，慢慢地催开了我心底那美丽的花儿。 老师，您是否还记得那次午休?同学们都伏在课桌上睡觉，后来外面下起了雨，阵阵凉凉的风吹进教室，吹乱了您的头发，也吹乱了同学的衣裳。您正想起身做点什么，突然您好像想起了什么，又坐了下来——噢!只见您脱下了您的高跟鞋，轻轻地走到窗户边，悄悄地把每一扇窗户都关上了。啊!老师，您是怕吵醒了那些可爱的熟睡的孩子呀!老师，您知道吗?那一刻，我觉得自己就像是一个孩子，生活在母亲的怀抱。那一刻，我觉得您就像一 股春风，悄悄从我们身边吹过。 老师，您可曾想起那个炎热的下午?我们在楼梯口相遇，我道了一句“老师好”，您甜甜一笑，走过来，轻轻地拉了拉我的衣领：“热不热?”突然，您发现我的脖子上那些红肿的小疱，您关切地问：“呀!这是怎么回事，蚊子咬的吗?”我点了点头。没想到第二天早上，您就给我带来了驱蚊花露水。那一刻，我又惊讶又感动。望着同学们羡慕的眼光，我的心底仿佛拂过一缕春风，温暖而幸福。 老师，您是否记得那次晨读?同学们都在教室里认真地读书，忽然，我感觉有个身影从我身旁走过。一抬头，我才发现桌子上多了一瓶牛奶，上面还有几个有趣的字“喝了长高噢”。再朝那个身影望去——乌黑笔直的秀发飘在肩后，我知道，是老师您。 老师!您知道吗?在住校的那段时间，我时常会记起您，我时常会抱着那花露水瓶子睡觉，我时常会穿着您送我的带着香味的衣裳…… 一阵春风轻轻拂过，我仿佛又看到了您那熟悉的身影。 春风拂面 岁月是爱人的，每年，即使春已逝去，也会在某一个时候给人以春风拂面的感动。 我平时喜欢写作文，语文老师就鼓励我向报刊投稿。“我?能行吗?”看着老师坚定的眼睛，我下定了决心。但是一次又一次的石沉大海，我又开始灰心了。 “来，文章见报了……”声音温和，是语文老师。似乎早有预感，庆幸却又疑惑。我已忘了自己还死僵僵地坐在座位上。老师满脸笑容地离开了。“真没礼貌!”身旁的男生嘀咕道。这才醒悟：我，就是一个忽视了最简单的礼貌的人。 仿佛为我的坏心情应景一般，风儿大了，调皮地飞驰而过，掠走了我的微笑。上课后，老师就就一些难题向我们指点迷津。教材第110页……”黑板上显现出一行醒目的大字。还没等老师说完，我就心急火燎地开始复制克隆，笔走龙蛇。不料被老师撞见，批评了一句：“做题时要看清题目，再去对照答案……当时，真是无地自容，还是科代表呢!名不副实。这才明白：我，就是一个冒冒失失的人。 下课的时候，狂风骤起，刹那间将我无奈的寂寞卷入云层。学习上的退步，甚至让我怀疑自己就是一个超低智商的人。于是，一次次地摔跤、失落、放弃、流泪。感觉生活就是一座幽深的城堡，欲离去却始终找不着方向。可是，在晚饭时，当妈妈把熟悉的饭盒递到我手中，接着是匆忙的问候，我忘记了吃饭，那一刻，忽然感觉到如春风拂面，幸福无比。 我总是这样，预先准备了对待苦难的从容，却没学会从苦难中体验快活，总是注重自己的感受，却忽视了身边一直伴随提醒我的亲人朋友。同学的良言规劝是幸福，老师的悉心开导是幸福，亲人馈赠的欣悦是幸福……这样的幸福太多太多。 一路上，被人提醒，如沐春风。 [点评]这篇文章在选材时注重了“小处着眼”，写生活中时时处处有人提醒：忽视礼节，冒冒失失，忘记吃饭，这些琐碎的生活片段，写出了对生活深层次的感悟，紧扣“提醒”，揭示主题：原来，生活中有了提醒，是一种莫大的幸福。 春风拂面 春风，在我心目中是最纯洁、最高尚的。它从容淡定、缥缈虚无，同时又是世间自由不羁的精神所在，亦如那些从历史里缓缓走来的身影…· 那不羁的风，我想，是李白吧!他有"飞流直下三千尺，疑是银河落九天"的气魄，他有"仰天大笑出门去，我辈岂是蓬蒿人"的潇洒，他有"安能摧眉折腰事权贵，使我不得开心颜"
中学请假条范文3篇_请假条 阁巷中学学生出校门请假条(表一) 班级 姓名 事由及去向： 离校(班) 时间月日时分 大约所需 时间 家长 联系电话 申请人签名_______________ 年月日 (此表由请假学生本人填写，准假人员留下存档) ……………………………………………………………………………………………………
阁巷中学学生出校门证明(表二) 班级 姓名 事由及去向： 离校时间 月日时分 回校时间 (门卫填) 月日时分 门卫签名__________ 准假人员签名_______________ 年月日 (此表只能由准假人员填写，学生凭此条出校，回校时由门卫填好回校时间后留存) 阁巷中学学生出校门请假条 中学生请假条主要结构范文 中学生请假条主要结构范文 1.居中写标题请假条“请假条”，这是所有应用文的通用
要求，用来表明此文是用来请假的条子! 2.请假对象的称呼，要请假必须得到批准，这个地方往往是老师、领导等，这个地方要尊称喔! 3.请假原由，这个地方要实事求是，否则后果自负! 4.请假起止时间，这个非常重要，必须重点提出，明确。 5.祝颂语。祝福对方，这个是所有公文里表示对对方的友好。 6.请假人签名。你自己的签名，一般不用按手印，只需要签即可。 7.请假时间。当前你写请假条的时间。 高中学生请假条格式模板 请假条 尊敬的老师： 本人因需向您请假天(节) ，请假时间为：20 年月日午第节至20 年月日午第节。特此请假，恳请老师批准! 此致 敬礼! 请假人： 请假申请时间：20 年月日
本人联系电话： 家长电话： 班级：请假类别：□ 病假□ 事假(已请示班主任同意)班长证明签：班主任(科任教师)意见及签： 备注：学生办完事应及时回校，不得在外逗留，否则，将做严肃处理，学生离校期间一切安全事故自行负责。 中学生请假条的样本 请假条 尊敬的______老师： 我是_____________初\高______级_____班学生__________，因_____________________，特向您请假___________(多久)，请假时间为_______年____月_____日_________至__________。离校期间一切安全责任由我(学生本人)自负，请您准假! 教师意见： 请假人：___________ _______年____月_____日
小学语文《想象作文》教案设计之一 小学语文《想象作文》教案设计之一 一、教学目的 1．启发学生自由地想象，培养学生的创新思维能力。 2．指导学生有序地、重点突出地、主次分明地说和写。 3．培养学生热爱学校、热爱生活、热爱科学的思想感情。 二、教学重点 启迪学生展开大胆、丰富、新奇的想象，并指导学生有序地、主次分明地说和写。 三、课前准备 1．课前学生绘制自己心目中《未来的......》构想图。 2．制作多媒体课件。 四、教学时间 二课时（第二课时为写作及讲评） 五、教学过程 第一课时 （一）导入
1．谈话：(出示课件1后)小的时候，我就曾经幻想过，如果我能够像小鸟一样，有那样一对翅膀，那该多好啊！现在你们又有怎样的想象呢？（板书：想象） 2．结合学生回答表扬“你的想象真大胆！”.“你的想象真丰富！”.“你的想象真新奇！”（教师板书：大胆.丰富.新奇） 3．小结：希望同学们能把大胆.丰富.新奇的想象，在自己的作文中体现出来。（4分钟） （二）本次作文指导经过。 1.让我们乘上宇宙飞船，穿越时空隧道，去未来看一看吧！（出示课件2）（1分钟） 2.我们还在去未来的路上，但是伟大的科学家爱因斯坦曾经说过：“想象是一切创造之源。”（出示课件3）这节课让我们用想象创设一下未来吧！同学们，今天这节课，我们就来写一写未来的......（板书：未来的......）（出示课件4）（1分钟） 1．读一下课题，你觉得可以写什么？进行讨论。（3分钟） 提示：人物、事物、军事、科技、农业、环境、体育等等。 估计可能有的题目：《未来的我》、《未来的生日》、《未来的母校》、《未来的教师》、《未来的祖国》，以及《未来的地球》、《未来的汽车》、《未来的学校》。 明确：在现实生活的基础上，随着科技发展，将来可能实现的设想或可能拥有的事物才可写。 2．我们选好了要写的题目，那么怎么来写，具体写些什么呢？ 3．学习小组进行讨论，要求：
25. 第一部分听力(共两节。满分30分) 第一节(共5小题；每小题l．5分，满分7．5分) 听下面5段对话。每段对话后有一个小题，从题中所给的A、B、C三个选项中选出最佳选项，并标在试卷的相应位置。听完每段对话后，你都有l0秒钟的时间来回答有关小题和阅读下一小题。每段对话仅读一遍。 1．What is the probable relationship between the speakers? A. Father and daughter． B. Doctor and patient． C. Teacher and student． 2．Why can’t the machine work according to the woman? A．The power may have been cut off． B．There is something wrong with it． C．Both of the speakers can’t operate it． 3．What does the woman mean? A She is tired of keeping pets． B She wants to have a dog． C She won’t have a dog as a friend． 4．What can we learn from the conversation? A．The man will invite Mary to dinner． B The man will buy his daughter a gift． C．Mary has a lovely girl． 5．Which of the following does the woman like best? A. Fishing．13．Swimming．C．Climbing． 第二节(共15小题；每小题l．5分，满分22．5分) 听下面5段对话或独白。每段对话或独自后有几个小题，从题中所给的A、B、C 三个选项中选出最佳选项，并标在试卷的相应位置。听每段对话或独白前，你将有时间阅读各个小题，每小题5秒钟；听完后，各小题将给出5秒钟的作答时间。每段对话或独自读两遍。 听第6段材料。回答第6，7题。 6．What season is it now? A Spring． B Summer． C Autumn． 7．What will the speakers do? A. Drive to San Diego． B．Have take—away food in the park． C. See an outdoor movie． 听第7段材料。回答第8,9题。 8．What color is the tie the man is looking for? A. Green． B. Blue． C. Brown．
常用学生请假条格式范文_请假条 (二)学生请假条 尊敬的______老师： 我因____________(请假缘由)，无法在准时到校上课。特此向您请假____________(请假时间)，望您批准，谢谢您的理解和帮助。 此致敬礼! 学生： 年月日 (三)学生请假条 尊敬的______老师： 我是_____________初\高______级_____班学生__________，因_____________________，特向您请假___________(多久)，请假时间为_______年____月_____日_________至__________。离校期间一切安全责任由我(学生本人)自负，请您准假! 教师意见：______________ 请假人：___________ _______年____月_____日 (四)学生请假条 我是_______级本科生_______(姓名)，学号_______，因_______(事由)需请假，离校时间_______年_____月_____日_____点_____分，预计返校时间_____ 年_____ 月_____日_____ 点，离校期间联系方式_______________ 。本人已接受辅导员的安全和纪律教育，保证按时返校，请假外出期间个人一切安全责任由自己负责。 __________ 请假人： 时间： 请假条存根 我是_______级本科生_______________ (姓名)，学号__________ ，因_________________________ (事由)需请假，离校时间__________年_____月_____日_____点_____分，预计返校时间_____ 年_____ 月_____日_____ 点，离校期间联系方式_______________ 。本人已接受辅导员的安全和纪律教育，保证按时返校，请假外出期间个人一切安全责任由自己负责。 __________ 请假人： 时间： 附：学校学生请假制度 一、请假条由政教处统一发放到班主任处，请假均需要先到班主任处领取请假条，填写完毕，经班主任批准，方可请假。 二、因故不能自己来请假或来不及请假的，回校第一天马上到班主任处签字补假。 三、学生事假应持有家长证明书，病假应持医疗单位证明。一天以内由班主任审批，叁天内由政教处审批，叁天以上由校长室审批。 四、各班考勤员必须记录每天上课、自修和其他集体活动的出勤情况。周五下午将考勤表送交政教处，周一早上领取。
三年级下册语文第五单元作文《奇妙的想象》写作指导 一、审题 写一个想象故事。展示自己的奇妙想象，创造出属于自己的想象世界。 二、选材 写想象的故事。，而不是现实生活中的事，如矮人国的故事、大熊开面馆的故事、小狗变巨人、我有魔法了……只要是你能想到的故事都可以。 三、构思 我们以《最好玩的国王》为例进行构思，简要列出习作提纲。 开头：交代国王的爱好：微服私访。(略) 中间：微服私访时发现了一本畅销书，他大受启发，自己也写了一本书，后来这本书也非常畅销。(详) 结尾：交代畅销的原因：这本书太无聊，人们买来治疗失眠。(略) 四、表达 ①为习作起一个有趣的名字，如《播种女巫》：②大胆想象，让想象的内容神奇、有趣；③记得上自己平时积累的一些好词佳句哟！
写作素材 一、题目 《瞌睡虫多多》《小豆苗历险记》《白雪公主后传》《月亮又瘦了》 二、好词 无影无踪大摇大摆活灵活现转瞬即逝 神秘莫测窃窃私语一模一样大吃一惊 远走高飞 三、好句 开头 1.晚上，一道金光闪过，我突然发现睡在身边的妹妹变成了一个巨大的金蛋。我急坏了，怎么才能把妹妹救出来呢?把蛋砸破，可能会伤到里面的妹妹。把蛋刹开妹妹会不会变成蛋清流出来呢?我想了又想，最后决定把妹妹从蛋里孵 出来。 2.在离天河不远的地方，有三颗小星星。说来也巧，这三颗小星星是同年、同月、同日、同时生的，可它们彼此都不一样：一颗是蓝的，一颗是红的，第三颗最小，似乎没有什么颜色，只有一点儿微弱得可怜的光。 结尾 1.从此，绿森林里多了一个永久性的居民，绿森林的动物们多了一个永远的朋 友，绿森林的故事里多了一份传奇。 2.大力士风孩子回来了，呼呼吹了几口气，白烟被吹跑了，烟筒和房子被吹倒了那几个黑衣人被吹到了森林外。大树们开心地笑了。
福州格致中学2015级高一学段第一学期质量评定 高一年级第五次月考英语试卷 时间：100分钟分值120分 ★祝考试顺利★（完型填空启用备用卷题号不同答题卡区域注意区别） 第Ⅰ卷选择题（共两部分，满分70分） 第一部分阅读理解（共两节，满分40分） 第一节、完形填空（共20小题；每小题1.5分，满分30分） 阅读下面短文，从短文后所给各题的四个选项（A、B、C和D）中，选出可以填入空白处的最佳选项。 Most of us are highly aware of various channels through which we can obtain information on food safety. A majority of us have shown much __36___ in experts and authorities and taken a(n) __37___ part in science activities organized by such experts. __38_, we do not always form an accurate picture When there is __39_news about one brand, our trust in all brands or similar products tends to be __40___ . We would doubt not only the brand in __41___ but also similar brands when a safety issue (问题）_42___ in the news. At the same time，our purchase __43___ change as food safety incidents occur. We are becoming _44___ confident in domestic(国内的）food companies ，for they have done too little in publishing and sharing food safety __45__ so far. As a result ，we would turn to __46__ brands more often. Food safety incidents in China have attracted a lot of attention. As a matter of fact ，we only have a very _47__ knowledge base on the issue. In developed countries，there have been relatively _48__ measures and response system toward safety issues. Therefore, the __49___ in those countries are less likely to become over-panicked and form serious _50 about all brands. Food companies should pay more attention to our insights, listen to our voices, _51___ the opinions of experts and authorities ,have effective strategies for response _52____ various media channels, and __53___ information in time and face the public honestly. In addition ，both the government and an independent third - party should have a role to play in providing information about food companies__54___ in raw material selection, production and distribution (流通) However, this might require several years and we still need to learn more about food __55___ 36. A. respect B.enthusiasm C. distrust D. confidence 37. A. slight B. broad C. active D. natural 38. A. However B. Consequently C. Meanwhile D. Furthermore 39. A. negative B. exciting C. detailed D. special 40. A. protected B. affected C. increased D. preserved
关于春风的作文（6篇） 【第1篇】关于春风的作文：春风赞 所谓的春风，如此温柔。瞧！春风轻吻着柳枝，柳枝有节奏地摇摆着，摆动着它那细腻的腰姿，微微地吹皱了水面，偷偷地传送着花香。如此温柔、如此温柔，就像万物的母亲，无微不至地亲切体贴着万物，让万物生机勃勃地活动着。微风吹拂着千万条嫩黄色的柳枝，为它们换上了新衣裳；迎春话、牡丹花……春风吹拂着那娇媚的花儿，人们不由得分外爱惜！ 一切万物只因它！ 它就像一位慈祥而细心的“母亲”，她辛勤地培育着“儿女”，用她那甜美的乳汁来赋予营养给儿女，为的是什么呢？她为的是给儿女更好的东西、更好的生活和更好的体魄。儿女长大了，母亲给了他们最好的教育和贴心的爱护。如今儿女已经可以挣脱开母亲的怀抱，展翅飞翔，翱翔在天空中，那这些功劳归功于谁呢？一切都是母亲在儿女的背后默默支持的结果。 春风仿佛是一种生命的动力，它可以唤醒万物，也可以成为人的力量。春风扑面而来，使我想起了“一年之季在于春”春给人带来了新的一年，新的希望，新的人生目标……一阵春风吹来，我的头脑顿时清醒了，明白了人不仅要学，还要懂得运用。用春风来唤醒自己心中的渴望，让它告诉自己应该努力发奋，为自己的渴望而发奋实现
这美好的愿望。所以我们要珍惜这种源之动力之风。 春风如此温柔、如此细腻，怎能不让人心动去珍惜呢？让我们一起珍惜这股动力之风吧！ 【第2篇】关于春风的作文：春风拂面 春天来了，太阳公公擦擦自己的眼，戴上眼镜，俯瞰世界，感叹：“这会是美好的一天。”风姑娘轻悄悄地来到了人间，用手轻抚柳树姑娘的头发，柳树姑娘醒来了，才发现这时的头发被某人梳理了一下，风姑娘摸着小草的头，轻声说：“该起床了！”这时，小草睡眼惺忪的睁开了眼睛，伸了伸懒腰。不一会儿，世间万物都从睡梦中醒来了。 她在床上熟睡，“起来，快起来！”闹钟好不耐烦的叫着，她醒了来“哎！好梦就这样被破坏了！”迅速的穿好衣服，急匆匆地走到了学校。她从书包里拿出书，大声朗读书中的内容，读着读着，就觉得有点困，本想伏在桌上休息的，她看到成绩比较好的来到了教室，她于是从书包里来翻到有问题的一页，走到他们面前寻求解题思路，问题进一步得到解决。此时春风拂面，振作了他疲惫的精神。 他和同学坐在一起，它却只能沉默过眼地陪伴这同学，他深感歉疚，同学忍不住要和他讲话，她在旁边认真地听，认真的回答他们提出问题，把心中的烦恼全部说出来了。心中舒服了好一阵子。这时春风拂面，排除了她心中的烦恼，则多了一份快乐。 从窗外望——处处都充满绿色，五彩缤纷的花点缀着绿，小鸟
学校请假条范文 请假条 敬爱的老师: 您好!由于我晚上要在公司上班,晚上不能去上课了,请您批准! 请假人:某某某 时间 请假条 敬爱的**老师: 我是**学院**级学生,学号:******,因**************将于****年**月**日至****年**月**日外出,****年**月**日**点返回学校,目的地*******,外出期间联系方式********,在外出期间自身人身财产安全由本人负责,我将注意安全,按时返校. 学生:*** ****年**月**日 尊敬的老师您好: 我是xx班的学生,平时也是按时的遵守学校的各项规定，从不敢逾越。然而，现在我却不得不向您请假。因为我哥要结婚。结婚是人生的一件大事。我不想让哥哥和我留夏什么遗憾。而且，父母，亲人，和哥哥都希望我能出席婚礼。于情于理，身为兄弟的我要出席哥哥的婚礼。在此，我诚恳的期望老师您能批准我的请假要求。向您保证，我会在规定的时间内赶回学校的。 尊敬的学校领导(或x校长): 您好 我将于近日结婚,婚期定在*月*号.是老人家定的.我也借此机会向您报告.因为最近比较忙,结婚的很多事情都没有怎么准备,双方父母催得特别紧,几次打电话要我赶紧请假去办.要我*月*日--*日务必去做必要的准备工作. 现在正置期末,学校和班里的工作又比较繁忙,真是不好意思向您说请假的事.万望您海涵准假. 谢谢
请假人 xxx 请假条 尊敬的老师： 您好!我是06级电子商务专业直属班的学生，因为，需要请假(时间)从到，去往地点，请假期间有效联系方式：。 本人保证往返途中的个人人身和财产安全，在不耽误学习课程和任何集体活动的前提下，恳请您批准，谢谢! 班长(副班长)意见: 班主任意见： 本人签名： 日期： dear mr. liu, i’m li jun’s mother. i’m writing to ask for permission for li jun’s absence. the fact is that he has to stay at home to take care of my mother who had a serious fall from upstairs and got her right leg broken last week. i’m sure he will be back in three days when my husband returns from a meeting in beijing. thank you. sincerely, li yihua 请假条 敬爱的老师: 您好!由于我晚上要在公司上班,晚上不能去上课了,请您批准! 请假人:某某某 时间 请假条 敬爱的**老师:
小学语文想象类作文的构思技巧整理 给文字插上想象的翅膀，想象类作文的构思技巧整理！ 学生在作文时，往往觉得没有合适的素材可写，或是不知从何想象。其实呢，不是生活中没有作文素材，而是学生缺少善于捕捉作文素材的能力。连素材都有限，自然就很难展开想象了。因此，培养学生的观察生活的能力，养成留心观察周围事物的习惯显得十分重要。 01 怎样指导孩子观察呢？ 1．观察周围尽可能看到的所有事物，捕捉典型材料。 孩子的视线往往局限于一个小圈子，觉得一些司空见惯的小事没什么可写的。其实，平常的小事也可写出新意来。要选择最佳的观察对象，安排合理的观察顺序，认真观察。2．动用多种感官，丰富写作素材。 心理学认为，观察是思维的知觉，没有思维的观察是肤浅的，不是真正的观察。观察不仅仅是看，要动用耳、口、鼻、手、脑等感官去多方面地感知或判断，获得真实、全面、深刻的印象，为作文提供丰厚的材料。3．填写观察记录，养成观察习惯。 观察不应只是一次作文之前的例行公事。还应填写观察记录（观察顺序、观察方法）。 02 如何构思 以《卖火柴的小女孩》为例题，小女孩五次擦燃火柴所看到的奇异景象是作者的想象。这些想象奇特而大胆，而读者仍然觉得合情合理。
为什么呢？因为作者亲眼目睹了穷苦孩子的悲惨遭遇，深深地理解他们的内心需求。在文章中，想象与现实有着相似的地方，那就是穷孩子对幸福生活的渴望。 作者想象小女孩在神志不清时见到了温暖的火炉，喷香的烤鹅，美丽的圣诞树，慈祥的奶奶并和奶奶一起飞走，就显得自然而合理了。 无论写哪类想象作文，我们都必须做到以现实生活为基础，想象要合理、丰富，表达要真实、具体。 03 以现实生活为基础 现实生活是我们想象的源泉，离开了现实生活，想象就如同空中楼阁，成为无本之木、无源之水，变成空想或幻想。 所以，写想象作文必须勤于观察，丰富自己的生活，积极思考，驰骋想象，创新思维，这样才能引发你进行写作的灵感，进而写出优秀的想象作文。 04 怎样做到想象合理、丰富呢 1．再现 侧重于写景状物或叙事的想象作文，可以搜寻脑海中对相关事物的印象，加以再现。2．移植 有时候，想象可以进行嫁接、移植，把优美的景色移为一处，或把有趣的现象归为一物，或把美好的品质浓缩在一人之身。即，学生可以按自己的意愿中的特定形象，结合生活实际，进行移植想象。只有善于把想象与现实生活中的事实联系起来，巧妙地设计人物之间的关系，才能使文章生动有趣。3．幻想
春风送暖，如丝般的触感滑过脸际，送来温暖的气息。像圣洁的天使飘落的羽毛，又似冬日的火光映照着脸颊，勾起心底潜藏着的那暖暖的记忆。 “怦”，好险，好险。将将赶上这班车，不然，可又得等上半小时呢! “呼”，长舒一口气，抓好扶手。提着袋子，心头嘟囔：大夏天的还得去给表弟送书，什么世道，补课竟然都不带书，学的好才怪!心里愤愤的咒骂着。 “喂，我说这个女生，不想买票哟!”售票员不耐的声音总算唤回了我的神思。吐吐舌头，开始找钱包、掏钱、买票。等等!我钱包呢?糟了，莫不是跑得急忘在家里了?! 天哪，别开玩笑了。不过很可惜，上帝爷爷今天似乎睡觉去了，我全身上下摸不出一毛钱。 售票员看着我着急的样子冷笑着：“你这样的学生我见多了，什么‘钱包没带’‘钱掉了’的，我听得多了。小小年纪什么不学，学人家坐霸王车，害不害羞哟。撒起慌来脸都不红，羞不羞!” 我长这么大，什么时候被这样当众骂过。委屈的泪水一下子涌上了眼眶：“阿姨，对不起，我下车总行了吧。” “哟，装撒。现在的小孩哟，太会演了，怕是都已经到了要去的地方了吧。” 我咬着唇，拼命忍住眼里酸涩的泪水，自知理亏，也没办法反驳。 “阿姨，她是个女生，不过忘了带钱嘛，谁不没有点难处。你话也不能这样说啊。不就一块五嘛，我帮她买了。” 闻言侧头，身边是个和我差不多大的男孩儿。看着我，他轻轻眨了眨眼。清澈的目光既像关心，又像安慰，却更像春风拂过面庞，在炎炎夏日里带来阵阵温暖的清凉。眼里充盈的泪水，在此时，落了。 “谢谢，你叫什么名字。”我低低道着谢。 “呀，我叫什么呢?嗯，说‘雷锋’太老土了。有了!”他故意顿了顿，眼里满是狡黠，“我叫‘春风’。呵呵……” 春日，细雨蒙蒙。我望着窗外如丝般的雨，发着呆。忽的，我的童年记忆像一缕春风拂面而来，将我带回童年时代……
小学语文教学论文：想象作文教学浅谈 作文是语文教学的重点，也是难点，而想像作文更是难中之难，小学生大都有“恐作症”，老师也常常为此头疼不已。那么怎样才能让学生在想象作文中有内容可写，有话可说呢？我认为可以从以下几方面训练。 一、观察现实生活，激发相关想象。 想像离不开现实，离开现实的想象是空洞的，无论哪一类想象作文都脱离不了现实生活。例如童话式想象作文，它是根据小学生喜爱动物的特点，用动物代替人类的形象来表达他们对世界的认识，在想像力作用下的动物附上了人的动作、语言、神态和思维。这类作文实际上是对现实的再现。 如想像作文“未来的×××”，这一类写未来生活的想象作文对学生而言有难度。未来是什么样的，学生除了接触到一些科幻片、科幻小说以外，其他的十分抽象，不知如何写。教师可引导学生仔细观察现实生活，展开想像的翅膀。例如现在的房屋，一旦完工，它便固定下来。如果让学生大但想象，让未来的建筑由一个个组装件构成，根据不同的需要进行不同的组合，这样既适合不同人的需求，又便于搬迁、移动，还可以维修，那该多好。又如当看到学校操场只有一处，空间过于狭小时，可以引导学生想象地下或空中操场，用电梯或升降机来回启用……这些现实中人们追求的更加便捷、完美的东西，都可以大胆想象它的样子、形状、功能。如果激发了学生想象的火花，那么展现在学生面前的空间不知有多大！ 二、结合课文内容，进行再造想象。
课文是学生学习文化知识的重要材料，也是学生写作的典型范例。教师可充分利用课文资源，结合课文内容，让学生练习改写、续写、扩写等想象性作文，是一种行之有效的再造想象途径，能有效提高学生的想像能力。 例如《凡卡》一文，当凡卡满怀希望地把信寄出去后，爷爷能收到吗？爷爷在乡下会怎样想念凡卡呢？小凡卡后来的命运又会如何呢？让学生大胆去想象，续写出符合事情发展的故事，这样既加深了对课文内容的理解，又激活了学生想象的火花。 另外，还可以根据文中的插图进行补充或扩写。如《我的战友邱少云》一文在的插图，邱少云被烈火烧身时的巨大痛苦，是通过作者的心理活动侧面描写的，那么邱少云的心理感受会怎样呢？可引导学生观察他的神态、动作进行想象。 三、填补一些空白，设置整体形象。 在教学中选取一些相关的事物或词语，让学生进行整合，填补其中的空白，也是提高学生想象能力的重要手段。例如：画下几种不同的小动物，让学生按照自己的思维说出它们之间的关系，并想象出这些小动物之间会发生什么样的故事，然后进行口述表演，这样激起学生的童趣，他们的想象力就会更活跃。或者随便写下几个词语，让学生编上一段故事，用上这几个词语。这类填空白的训练，可以让学生的想象能力得到逐步提高。坚持长期训练，会收到意想不到的效果。 总之，学生作文能力的提高与教师的训练密不可分。我们应该在平时的作文教学中善动脑子，力求科学、有效，为学生作文插上想像的翅膀，让他们飞得更高、更远。
【篇一】一缕春风拂面来初三作文800字 无论冬天怎样漫长，春天就如同樱花般总会熬过严冬，以最美的姿态绽放于枝头，与你相见。——题记 20XX年的冬天似乎格外漫长，一场突如其来的新冠肺炎疫情袭卷神州大地。原本热热闹闹的新年，突然变得冷冷清清，和煦的春风也被阻隔在口罩之外。 出于安全考虑，人与人之间时刻注意保持安全距离，每个人的微笑也被隐藏在口罩之中。有一天上完网课，有些疲惫的我抬头看向窗外，突然发现门前的那棵树居然长出了嫩芽。之前因为功课太繁忙，每天早出晚归，披星戴月，所以从未注意到窗前的那棵树。今年春天延迟开学，我在家里上网课，所以有幸能见证它的生长。 那些刚刚长出的幼小嫩叶簇拥在一起，就像一朵小小的绿色荷花。那绿就像被雨水冲洗过一般，即使身在火热的夏天，也能让你的心底泛起一阵清凉。生命有时很脆弱，也许一场大雨就能把这些嫩叶摧残，可生命又如此顽强，即使被暴雨摧残，它们依旧能够长出新芽，继续生长。我们人类又何尝不是这样呢? 也许无情的病毒会夺走我们的生命，但是我们有能力、有信心从死神手里抢回。在这场人与病毒的战争中，我们看不到硝烟四起，但每天都有生死离别，阴阳两隔。疫情发生以来，每个人都在全力为抗疫作贡献。你看，爱与希望总比死亡与病毒蔓延得更快，这就是生命的张力与尊严。回顾历史，人类经受过很多苦难，在苦难面前，生命是何等渺小，但我们从不放弃活下去的希望。即使在苦难中，我们也艰难地摸索前行，去等待属于我们的春天，去感受那春风拂面的温柔。 这个春天，即使我们遭受过挫折，但生命却不会因为这些挫折而停滞，相反，它会拼命生长，在苦难中开花、结果。我想每一个熬过冬天的种子都有一个春天的梦想。让我们再等等，等到这个春天真正的到来，等到所有的花儿都开放，等到看樱花的人比樱花还要多，等到和煦的春风又再次抚摸脸颊。我们一定会摘下口罩，微笑问好。 【篇二】一缕春风拂面来初三作文800字 春风拂面，在其他任何季节，也会有一番如沐春风的舒畅与感动。 冬，一个寒冷的冬日，呼呼的寒风猛烈地刮着，呵气成冰的天气让我倍感不适，我因病体育课时在班中休息，听着外面强烈的风声，望着自己已冻得通红甚至有些僵硬的手，不禁一阵猛搓。这是，老师轻轻推开了门走了进来，端来一杯热水，关切的问道：“感觉好些了吗?喝点水，暖暖身子，如果不舒服直接去办公室打电话啊，不用找我。”我点点头，喝着水，感到无比的暖意，在这寒冬，我有一份感动，如同春风拂面。 不仅是在冬日，在夏日，也会有春风拂面的感觉。