1260 Rev Esp Cardiol. 2009;62(11):1260-6
Non-ST-Elevation Acute Myocardial Infarction With Normal Coronary Arteries: Predictors and Prognosis
Alejandro Cortell, Juan Sanchis, Vicente Bodí, Julio Nú?ez, Luis Mainar, Mauricio Pellicer, Gema Mi?ana, Enrique Santas, Eloy Domínguez, Patricia Palau, and ángel Llácer
Servicio de Cardiología, Hospital Clínico Universitario de Valencia, Valencia, Spain
ORIGINAL ARTICLE
This study was supported by a grant from the HERACLES Cardiovascular Research Network (RD06/0009 Ministry of Science and Innovation, Instituto de Salud Carlos III, Madrid, Spain). Drs Juan Sanchis, Vicent Bodí, Julio Nú?ez, Luis Mainar, and ángel Llácer also received support from a grant FIS PI070640 (Instituto de Salud Carlos III, Madrid, Spain). Correspondence: Dr. J. Sanchis.
Servicio de Cardiología. Hospital Clínico Universitario. Blasco Ibá?ez, 17. 46010 Valencia. Espa?a. E-mail: Sanchis_juafor@gva.es
Manuscript received November 28, 2008. Accepted for publication July 7, 2009.
Introduction and objectives. Occasionally, coronary arteries without significant stenosis are observed during invasive treatment of acute non-ST-elevation myocardial infarction (NSTEMI). The aim was to investigate predictive factors and prognosis in these patients.
Methods. The study involved 504 patients admitted for NSTEMI who underwent cardiac catheterization. The primary end-point was the observation of coronary arteries without significant stenosis, and the secondary end-point was death or myocardial infarction within a median of 3 years. In evaluating the secondary end-point, a control group of 160 patients with a normal troponin level and no significant coronary artery stenosis who were admitted for chest pain during the same period was included.
Results. Overall, 64 patients (13%) had coronary arteries without significant lesions. The predictors were: female sex (odds ratio [OR] = 6.6; P =.0001), age <55 years (OR=3.0; P =.001), and the absence of diabetes (OR=2.4, P =.02), previous antiplatelet treatment (OR=3.9, P =.007) or ST-segment depression (OR=2.4, P =.008). The composite variable of female sex plus at least 2 additional predictive factors had a specificity of 85% and a sensitivity of 53% for coronary angiography showing no significant stenosis. The absence of coronary artery stenosis decreased the probability of death or myocardial infarction during follow-up (hazard ratio = 0.3, 95% confidence interval, 0.2-0.9; P =.03). Among all patients without significant stenosis (n=224), there was no difference in the event rate between those with elevated and normal troponin levels.
Conclusions. In NSTEMI, female sex, age <55 years and the absence of diabetes, previous antiplatelet treatment, or ST-segment depression were all associated with coronary angiography showing no significant stenosis. The long-term prognosis in these patients was good.
Key words: Myocardial infarction. No significant stenosis on coronary angiography. Predictors. Prognosis.
Infarto de miocardio sin elevación del ST con coronarias normales: predictores y pronóstico
Introducción y objetivos. El manejo invasivo del infar-to agudo de miocardio sin elevación del ST (IAMSEST) detecta en ocasiones arterias coronarias sin estenosis significativas. Nuestro objetivo fue evaluar los factores asociados y el pronóstico de esta población.
Métodos. Estudiamos a 504 pacientes ingresados por IAMSEST y sometidos a cateterismo cardiaco. El objetivo primario fue el hallazgo de coronarias sin estenosis signi-ficativas y el secundario, la mortalidad o el infarto a una mediana de 3 a?os. Para evaluar el objetivo secundario, se utilizó un grupo control de 160 pacientes ingresados por dolor torácico durante el mismo periodo con troponi-na normal y coronarias sin estenosis significativas.
Resultados. Encontramos coronarias sin lesiones sig-nificativas en 64 (13%) pacientes. Los predictores fue-ron: ser mujer (odds ratio [OR] = 6,6; p = 0,0001), edad < 55 a?os (OR = 3,0; p = 0,001) y ausencia de diabe-tes (OR = 2,4; p = 0,02), tratamiento antiagregante pre-vio (OR = 3,9; p=.007) o descenso del ST (OR = 2,4; p = 0,008). La variable ser mujer con al menos dos va-riables adicionales identificó una coronariografía sin estenosis significativas con especificidad del 85% y sensibilidad del 53%. La ausencia de estenosis corona-rias significativas disminuyó la probabilidad de muerte o infarto durante el seguimiento (hazard ratio = 0,3; in-tervalo de confianza del 95%, 0,2-0,9; p = 0,03). En el total de pacientes sin estenosis coronarias significativas (n = 224), no hubo diferencias en la tasa de sucesos en-tre los pacientes con troponina elevada y normal.
Conclusiones. El sexo femenino, la edad < 55 a?os y la ausencia de diabetes, tratamiento antiagregante previo o descenso del ST se asociaron a una coronariografía sin estenosis significativas en el IAMSEST. El pronóstico a largo plazo de esta población fue bueno.
Palabras clave: Infarto de miocardio. Coronariografía sin estenosis significativas. Predictores. Pronóstico.
Cortell A et al. Non-ST-Elevation Acute Myocardial Infarction With Normal Coronary Arteries: Predictors and Prognosis
Rev Esp Cardiol. 2009;62(11):1260-6 1261
January 20, 2001 and April 1, 2008. The follow criteria had to be met for inclusion in the study: a) no persistent ST elevation in the initial cardiogram; b) elevated troponin I in successive measurements (on arrival at hospital and 8-12 hours after the onset of pain); c) no history of significant coronary artery stenosis determined by coronary angiography; and d) cardiac catheterization and coronary angiography during admission. The study population accounted for 62% of all patients admitted for NSTEMI without significant prior coronary artery stenosis recorded during the study period; the remaining 38% of the population did not undergo catheterization.
In our hospital, 2 different troponin I reagents were used during the study: Immulite (Diagnostic Products Corporation, Los Angeles, California, United States; upper limit of normal, 0.5 ng/mL) until October 2003 and Dimension (Dade Behring, Newark, Delaware, United States; upper limit of normal, 0.2 ng/mL) thereafter. The management of the patients and the indication for catheterization were according to the judgment of the attending cardiologist.
Variables Recorded
A range of clinical variables were recorded for each patient, including coronary risk factors (age, smoking habit, hypertension, hypercholesterolemia, diabetes mellitus, family history), history of myocardial infarction, peripheral artery disease, stroke, and prior antiplatelet therapy. From the electrocardiogram (ECG), an ST-segment depression was considered to be present for shifts of more than 1 mm in the initial ECG. In all patients, creatinine was measured on admission and renal failure defined as levels greater than 1.3 mg/dL. Coronary stenosis was considered significant if it exceeded 50% in one of the 3 main epicardial vessels or the left coronary artery. Objectives
The primary objective was to analyze the factors predictive of coronary events in patients without significant stenosis (lack of stenosis >50%). The secondary objective was to analyze total mortality or acute myocardial infarction during follow-up. The median follow-up period was 3 years (interquartile range, 64-184 weeks). Follow-up exceeded 6 months in 97% of the patients and 1 year in 91%. Control Group
Prognosis in patients with NSTEMI and normal coronary arteries was compared with that of a control group of 160 consecutive patients who were
INTRODUCTION
The rupture of an atheromatous plaque in association with a variable degree of thrombosis, in relation to a local inflammatory process, is the underlying origin of acute coronary syndrome.1-3 There is a certain range of severity of coronary lesions, as well as a range of thrombogenic response.4 Although acute myocardial infarction is generally associated with obstructive coronary artery disease, between 8% and 12% of patients have normal coronary arteries.5-12 The differences in prevalence between published series arise, in part, because of the characteristics of the population included, such as the type of infarction (with or without ST elevation), whether troponin levels are used to define the infarction, or whether unstable angina with normal troponin levels is included. In terms of prognosis, there is a certain heterogeneity in the results. Although prognosis is better for patients with obstructive coronary artery disease, there is a lack of agreement on the how benign the disease is.8,10-15 The lack of a control group with which to compare the natural history has probably helped fuel this controversy.
The objective of our study was to analyze the characteristics related to coronary angiography showing no significant stenosis in a consecutive series of patients with non-ST elevation myocardial infarction (NSTEMI), who underwent cardiac catheterization during admission to hospital. In addition, long-term follow-up was conducted and the factors related to prognosis were analyzed. Finally, the disease course was compared with that of a control group of patients who were admitted for chest pain of possible coronary origin and who had normal troponin levels and normal coronary arteries. METHODS Study Group
The study included 504 consecutive patients who attended our hospital for chest pain and were admitted with diagnosis of NSTEMI between ABBREVIATIONS
CI: confidence interval HR: hazard ratio
NSTEMI: non-ST-elevation myocardial infarction OR: odds ratio
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Cortell A et al. Non-ST-Elevation Acute Myocardial Infarction With Normal Coronary Arteries: Predictors and Prognosis
Cox regression (backward conditional method) with the variables of prognostic value in the univariate analysis. The hazard ratio (HR) and corresponding 95% confidence intervals (CI) were calculated.
Statistical significance was set at a value of P less than .05. The SPSS statistical analysis program, version 9.0 (SPSS Inc., Chicago, Illinois, USA) was used. RESULTS
Characteristics of the Study Population Table 1 shows the characteristics of the study population. Normal coronary arteries were observed in 64 patients (13%; 95% CI, 15.6-9.7). Sixty-five patients (13%) died during follow-up, 80 (16%) had an acute myocardial infarction, and 122 (24%) had an acute myocardial infarction or death. Factors Related to Normal Coronary Angiogram
Table 1 shows the differences in the baseline characteristics between patients with and without significant coronary stenosis. Table 2 shows the results of the multivariate analysis. Female sex was the variable most strongly associated with absence of significant coronary stenosis (OR=6.6; 95% CI, 3.5-12.5; P =.0001). Other variables were age less than 55 years (OR=3.0; 95% CI, 1.5-5.8; P =.001), absence of diabetes (OR=2.4; 95% CI, 1.2-4.8; P =.02), prior antiplatelet therapy (OR=3.9; 95% CI, 1.5-10.2;
admitted during the same period for chest pain of possible coronary origin according to the judgment of the duty cardiologist. These patients had normal troponin I levels, and the coronary angiography performed during their stay in hospital showed lack of significant coronary stenosis. In total, 37 patients showed ST-segment depression (>1 mm) in the initial ECG; 13 had a negative T wave (>1 mm), and 10 had left bundle branch block. Coronary angiography was done directly in 94 patients. For the remaining patients, prior to catheterization, exercise testing was done in 59 patients (28 with a positive result and 31 with an inconclusive result), and magnetic resonance imaging with dipyridamole in 15. The diagnosis on discharge was, in all cases, chest pain of unknown origin. Statistical Analysis
The variables associated with the primary objective were analyzed using the c 2 test. In order to transform age into a qualitative variable, its association with the primary outcome measure was analyzed using quartiles and the cutpoint corresponding to the upper limit of the first quartile (55 years) was chosen for its greater discriminative power. A multivariate logistic regression analysis was subsequently performed with the variables that were associated with the primary endpoint in the univariate analysis with P ≤.1. The maintenance criterion in the model was P <.05. Odds ratios (OR) and 95% confidence intervals (CI) were calculated.
For the secondary objective, a univariate analysis using a c 2 test was performed along with a multiple TABLE 1. Baseline Characteristics of the Patients With Non-ST-Elevation Myocardial Infarction and Prognosis According to Presence or Absence of Significant Coronary Artery Stenosis
Variable
Without Coronary Stenosis (n=64)
With Coronary Stenosis (n=440)
P
Age
60 (12.5) 66 (11.3) <.001Heart failure 3 (4.7) 49 (11.1) .128Men 27 (42.2) 325 (73.9) <.001Smoking 17 (26.6) 142 (32.3) .391Hypertension
33 (51.6) 264 (60) .222Hypercholesterolemia 23 (35.9) 205 (46.6) .139Diabetes mellitus
13 (20.3) 167 (38) .005Peripheral artery disease 0 35 (8) .015Creatinine on admission 0.98 (0.34) 1.13 (0.40) .007ST-segment depression 17 (26.6) 199 (45.2) .005Prior antiplatelet use
5 (7.8) 148 (33.6) <.001Family history of ischemic heart disease 4 (6.3) 39 (8.9) .634History of myocardial infarction 2 (3.1) 65 (14.8) .009History of heart failure 2 (3.1) 9 (2) .638History of stroke
2 (3.1) 30 (6.8) .408Acute myocardial infarction during follow-up 2 (3.1) 78 (17.7) .001Death during follow-up
2 (3.1) 6
3 (14.3) .009
Data are shown as means (SD).
Cortell A et al. Non-ST-Elevation Acute Myocardial Infarction With Normal Coronary Arteries: Predictors and Prognosis
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27%; P =.0001) after adjusting for other variables of prognostic value (HR=0.3; 95% CI, 0.2-0.9; P =.03) (Figure). The other associated variables were heart failure on admission (HR=2.6; 95% CI, 1.7-4.0; P =.0001), age (per year, HR=1.02; 95% CI, 1.0-1.04; P=.05), diabetes mellitus (HR=1.5; 95% CI, 1.0-2.2; P =.04), prior myocardial infarction (HR=1.6; 95% CI, 1.1-2.4; P =.03), and renal failure (HR=1.7; 95% CI, 1.1-2.6; P =.02).
The outcomes for the patients with NSTEMI and normal coronary arteries were compared with those of the control group. Table 3 shows the baseline differences between the 2 groups. Patients in the control group were older and more frequently had hypercholesterolemia and prior treatment with antiplatelet agents. Likewise, there was a tendency toward a greater proportion of men and systemic hypertension. During follow-up, among the entire population of patients with normal coronary arteries (n=224), 23 patients (10%) died or had an infarction. The death rates and rates of infarction in the subgroup with elevated troponin and normal troponin were 4 (6%) and 19 (12%) (HR=0.7; 95% CI, 0.2-2.2; P =.6). DISCUSSION
In our series, we found that 13% of the patients with NSTEMI lacked significant coronary stenosis according to the cardiac catheterization procedure performed during the initial stay in hospital. Female sex, younger age, absence of diabetes, and antiplatelet treatment prior to the infarction and presentation without ST-segment depression in the
P =.007), and presentation without ST-segment depression in the electrocardiogram (OR=2.4; 95% CI, 1.2-4.4; P =.008). The C statistic for the model with the 5 variables was 0.80, indicating an optimum predictive capacity.
In order to assess what proportion of patients were appropriately classified with the model, a variable indicative of high probability of coronary arteries without significant stenosis was created. This consisted of being a woman (given the greater OR) and at least another 2 of the 4 remaining variables. This variable identified a coronary angiogram without significant stenosis with a specificity of 85% and a sensitivity of 53%.
Prognosis of Acute Non-ST-Elevation
Myocardial Infarction With Normal Coronary Arteries
In the NSTEMI population, the lack of significant coronary artery stenosis was associated with a lower rate of death or infarction during follow-up (6% vs
TABLE 2. Variables Associated With Coronary Arteries Without Significant Stenosis
Variable
OR (95% CI)
P
Female sex 6.6 (3.5-12.5) .0001Age <55 years
3.0 (1.5-5.8) .001Without diabetes mellitus 2.4 (1.2-
4.8) .02No prior antiplatelet treatment 3.9 (1.5-10.2) .007No ST-segment depression in ECG 2.4 (1.2-4.4) .008
CI indicates confidence interval; ECG, electrocardiogram; OR, odds ratio.
A
B
100
200300
Weeks
8
64
2
P r o b a b i l i t y , %
+
+++
++++++++++++
+
+++++++++++++++++++++Death/Infarction
+
+++++++++++++++++++++++
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++Figure. Kaplan-Meier curves for death
or myocardial infarction according to presence of normal coronary arteries or significant stenosis. A: coronary stenosis; B: coronary arteries without significant stenosis.
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Cortell A et al. Non-ST-Elevation Acute Myocardial Infarction With Normal Coronary Arteries: Predictors and Prognosis
artery stenosis. Other associated factors were age less than 55 years, absence of diabetes, lack of prior antiplatelet treatment, and presentation without ST-segment depression in the electrocardiogram. The predictive model with these 5 variables showed an optimal discriminative power (C statistic = 0.80). In addition, we constructed a simple model consisting of an obligatory variable (female sex) and at least 2 of the 4 remaining variables. This simple model allowed us to identify a coronary angiogram without stenosis with good specificity (85%), although the sensitivity was low (53%).
Age and female sex are the predictive variables detected in other studies.8,11,17,19 In the PURSUIT study, a model was developed for predicting normal coronary angiography. This model included the variables of female sex, younger age, and absence of elevated necrosis markers, prior angina, diabetes, or ST-segment depression.11 In that study, unlike ours, patients were included without elevated necrosis markers. Prognosis
The lack of significant coronary artery stenosis was associated with better prognosis within the NSTEMI population. While there is agreement about the lower risk in patients with NSTEMI who have normal coronary arteries,15 their prognosis in the long term is subject of some debate.8,10-13,16,17,19,20 Thus, some series question the good prognosis of these patients.10,13,16 In our series, the long-term prognosis was better than that of the remaining patients with NSTEMI and similar to those of
electrocardiogram were the variables associated with coronary angiography showing no significant lesions. The long-term prognosis of this population was good.
Prevalence of NSTEMI and Normal Coronary Arteries
The frequency of myocardial infarction and normal coronary arteries reported in the literature ranges from 8% to 12%.8,11,12,16,17 The differences in prevalence between the studies could depend on the different characteristics of the populations studied. Thus, in some series, troponin is not used as a marker of necrosis while in others, patients are included if they have an electrocardiogram consistent with diagnosis of acute coronary syndrome in absence of elevated necrosis biomarkers. In addition, all studies represent the subgroup of patients with NSTEMI selected for catheterization, and the criterion used for this selection, whether broader or more restrictive, can also influence the angiographic results obtained. In the present study, diagnosis of infarction was done with troponin and catheterization was indicated in 62% of the patients with NSTEMI; this rate of catheterization is congruent with normal clinical practice in Spain for NSTEMI.18
Factors Predictive of Acute Non-ST-Elevation Myocardial Infarction With Normal Coronary Arteries
Female sex was the variable most strongly associated with absence of significant coronary TABLE 3. Baseline Differences Between Patients With Non-ST-Elevation Myocardial Infarction and Normal Coronary Arteries and Patients in the Control Group
Variable
NSTEMI (n=64)
Control Group (n=160)
P
Age, mean (SD), y 59.5 (12.5) 63.4 (11) .022Heart failure 3 (4.5) 4 (2.5) .41Men
29 (43.9) 92 (57.5) .078Active smoking 17 (25.8) 34 (21.3) .48Hypertension
33 (50) 102 (63.8) .073Hypercholesterolemia 24 (36.4) 92 (57.5) .005Diabetes mellitus
13 (19.7) 48 (30) .14Family history of ischemic heart disease 4 (6.1) 18 (11.3) .33History of myocardial infarction 4 (6.1) 16 (10) .45Prior antiplatelet use 7 (10.6) 56 (35) <.0001
History of heart failure 2 (3) 3 (1.9) .63Peripheral artery disease 0 5 (3.1) .32History of stroke
2 (3) 11 (6.9) .35ST-segment depression 17 (25.8) 37 (23.1) .73Baseline creatinine, mg/dL
0.98 (0.3)
1.05 (0.4)
.2
ECG indicates electrocardiogram; NSTEMI, non-ST-elevation myocardial infarction. Data are expressed as means (SD) or n (%).
Cortell A et al. Non-ST-Elevation Acute Myocardial Infarction With Normal Coronary Arteries: Predictors and Prognosis
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patients with chest pain, without elevated troponin levels and coronary angiography showing no significant stenosis. These data reinforce the good prognosis of this entity. Mechanisms
Several mechanisms might explain why some patients with NSTEMI had no significant stenosis in the coronary angiogram, such as for example, a thrombotic process that has already resolved when catheterization is done, microvascular dysfunction, or coronary embolism.19,21-24 This could also underlie substantial arterial disease that leads to an eccentric expansion of the atherosclerotic plaque that cannot be detected by coronary angiography.5-7 However, only a minority of patients have etiologic factors related to myocardial infarction and normal coronary arteries. Thus, a vasospasm test with ergonovine was positive in 15% of the patients and a coagulation disorder was detected in 12%.13 CONCLUSIONS
Clinical practice guidelines recommend an early invasive strategy in NSTEMI.25 In our study, we have found coronary arteries without significant stenosis in 13% of the patients with NSTEMI and associated factors have been identified. Likewise, a predictive model has been constructed. Although this information could be relevant for assessing the strategy of systemic cardiac catheterization in certain patients with a high probability of normal coronary angiography, the predictive model has not been compared with any external cohort, and so it is hard to gauge its true usefulness.Limitations
As the primary objective was to analyze the variables predictive of coronary arteries without significant stenosis, patients were excluded with a prior documented history of coronary artery stenosis. In addition, catheterization was indicated according to the judgment of the attending cardiologist. All these factors might have influenced the proportion of patients whose coronary angiogram showed no significant stenosis. Finally, the small number of patients in the group without significant coronary artery stenosis (n=224), where comparison is made with the subgroup with NSTEMI and the control group with normal troponin, means that any conclusions concerning the relationship with the prognostic value of troponin should be drawn with caution.
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A, Fernández-Avilés F, et al. Guía de práctica clínica para el diagnóstico y tratamiento del síndrome coronario agudo sin elevación del segmento ST. Rev Esp Cardiol. 2007;60: e1-e80.
18. Ferreira González I, Permanyer Miralda G, Marrugat J, Heras
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20. Dokainish H, Pillai M, Murphy SA, DiBattiste PM, Schweiger
MJ, Lotfi A, et al. Prognostic implications of elevated troponin in patients with suspected acute coronary syndrome but no critical epicardial coronary disease. A TACTICS-TIMI-18 Substudy. J Am Coll Cardiol. 2005;45:19-24.
21. Isner JM, Estes NAM, Thompson PD. Acute cardiac
events temporally related to cocaine abuse. N Engl J Med. 1986;315:1438-43.
with复合结构专项练习（二） 一请选择最佳答案 1）With nothing_______to burn，the fire became weak and finally died out. A.leaving B.left C.leave D.to leave 2）The girl sat there quite silent and still with her eyes_______on the wall. A.fixing B.fixed C.to be fixing D.to be fixed 3）I live in the house with its door_________to the south.（这里with结构作定语） A.facing B.faces C.faced D.being faced 4）They pretended to be working hard all night with their lights____. A.burn B.burnt C.burning D.to burn 二：用with复合结构完成下列句子 1）_____________（有很多工作要做），I couldn't go to see the doctor. 2）She sat__________（低着头）。 3）The day was bright_____.（微风吹拂） 4）_________________________，（心存梦想）he went to Hollywood. 三把下列句子中的划线部分改写成with复合结构。 1）Because our lessons were over，we went to play football. _____________________________. 2）The children came running towards us and held some flowers in their hands. _____________________________. 3）My mother is ill，so I won't be able to go on holiday. _____________________________. 4）An exam will be held tomorrow，so I couldn't go to the cinema tonight. _____________________________.
1. with+宾语+形容词。比如：. The boy wore a shirt with the neck open, showing his bare chest. 那男孩儿穿着一件衬衫，颈部敞开，露出光光的胸膛。Don’t talk with your mouth full. 嘴里有食物时不要讲话。 2. with+宾语+副词。比如：She followed the guide with her head down. 她低着头，跟在导游之后。 What a lonely world it will be with you away. 你不在，多没劲儿呀！ 3. with+宾语+过去分词。比如：He was listening to the music with his eyes half closed. 他眼睛半闭着听音乐。She sat with her head bent. 她低着头坐着。 4. with+宾语+现在分词。比如：With winter coming, it’s time to buy warm clothes. 冬天到了，该买些保暖的衣服了。 He soon fell asleep with the light still burning. 他很快就睡着了，（可）灯还亮着。 5. with+宾语+介词短语。比如：He was asleep with his head on his arms. 他的头枕在臂膀上睡着了。 The young lady came in, with her two- year-old son in her arms. 那位年轻的女士进来了，怀里抱着两岁的孩子。 6. with+宾语+动词不定式。比如： With nothing to do in the afternoon, I went to see a film. 下午无事可做，我就去看了场电影。Sorry, I can’t go out with all these dishes to wash. 很抱歉，有这么多盘子要洗，我不能出去。 7. with+宾语+名词。比如： He died with his daughter yet a school-girl.他去逝时，女儿还是个小学生。 He lived a luxurious life, with his old father a beggar . 他过着奢侈的生活，而他的老父亲却沿街乞讨。(8)With so much work to do ,I can't go swimming with you. (9)She stood at the door,with her back towards us. (10)He entered the room,with his nose red with cold. with复合结构与分词做状语有啥区别 [ 标签：with, 复合结构, 分词状语] Ciro Ferrara 2009-10-18 16:17 主要是分词形式与主语的关系 满意答案好评率：100%
基本用法 它是由介词with或without+复合结构构成，复合结构作介词with或without的复合宾语，复合宾语中第一部分宾语由名词或代词充当，第二部分补足语由形容词、副词、介词短语或非谓语动词充当 一、with或without+名词/代词+形容词 例句:1.I like to sleep with the windows open. 我喜欢把窗户开着睡觉。(伴随情况) 2.With the weather so close and stuffy, ten to one it'll rain presently. 大气这样闷，十之八九要下雨(原因状语) 二、with或without+名词/代词+副词 例句:1.She left the room with all the lights on. 她离开了房间，灯还亮着。(伴随情况) 2.The boy stood there with his head down. 这个男孩低头站在那儿。(伴随情况) 三、with或without+名词/代词+介词短语 例句:1.He walked into the dark street with a stick in his hand. 他走进黑暗的街道时手里拿着根棍子。(伴随情况) 2. With the children at school, we can't take our vacation when we want to. 由于孩子们在上学，所以当我们想度假时而不能去度假。(原因状语) 四、with或without+名词/代词+非谓语动词 1、with或without+名词/代词+动词不定式，此时，不定式表示将发生的动作。 例句: 1.With no one to talk to, John felt miserable. 由于没人可以说话的人，约翰感到很悲哀。(原因状语)
With的用法全解 with结构是许多英语复合结构中最常用的一种。学好它对学好复合宾语结构、不定式复合结构、动名词复合结构和独立主格结构均能起很重要的作用。本文就此的构成、特点及用法等作一较全面阐述，以帮助同学们掌握这一重要的语法知识。 一、 with结构的构成 它是由介词with或without+复合结构构成，复合结构作介词with或without的复合宾语，复合宾语中第一部分宾语由名词或代词充当，第二部分补足语由形容词、副词、介词短语、动词不定式或分词充当，分词可以是现在分词，也可以是过去分词。With结构构成方式如下： 1. with或without-名词/代词+形容词； 2. with或without-名词/代词+副词； 3. with或without-名词/代词+介词短语； 4. with或without-名词/代词 +动词不定式； 5. with或without-名词/代词 +分词。 下面分别举例： 1、 She came into the room，with her nose red because of cold.（with+名词+形容词，作伴随状语）
2、 With the meal over ， we all went home.（with+名词+副词，作时间状语） 3、The master was walking up and down with the ruler under his arm。（with+名词+介词短语，作伴随状语。） The teacher entered the classroom with a book in his hand. 4、He lay in the dark empty house，with not a man ，woman or child to say he was kind to me.（with+名词+不定式，作伴随状语）He could not finish it without me to help him.（without+代词 +不定式，作条件状语） 5、She fell asleep with the light burning.（with+名词+现在分词，作伴随状语） Without anything left in the with结构是许多英 语复合结构中最常用的一种。学好它对学好复合宾语结构、不定式复合结构、动名词复合结构和独立主格结构均能起很重要的作用。本文就此的构成、特点及用法等作一较全面阐述，以帮助同学们掌握这一重要的语法知识。 二、with结构的用法 with是介词，其意义颇多，一时难掌握。为帮助大家理清头绪，以教材中的句子为例，进行分类，并配以简单的解释。在句子中with结构多数充当状语，表示行为方式，伴随情况、时间、原因或条件（详见上述例句）。 1.带着，牵着…… (表动作特征)。如： Run with the kite like this.
With的复合结构 介词with without +宾语+宾语的补足语可以构成独立主格结构，上面讨论过的独立主格结构的几种情况在此结构中都能体现。 1. with+名词代词+形容词 He doesn’t like to sleep with the windows open. = He doesn’t like to sleep when the windows are open. He stood in the rain, with his clothes wet. = He stood in the rain, and his clothes were wet. With his father well-known, the boy didn’t want to study. 2. with+名词代词+副词 Our school looks even more beautiful with all the lights on. = Our school looks even more beautiful if when all the lights are on. The boy was walking, with his father ahead. = The boy was walking and his father was ahead. 3. with+名词代词+介词短语 He stood at the door, with a computer in his hand. He stood at the door, computer in hand. = He stood at the door, and a computer was in his hand. Vincent sat at the desk, with a pen in his mouth. Vincent sat at the desk, pen in mouth. = Vincent sat at the desk, and he had a pen in his mouth. 4. with+名词代词+动词的-ed形式 With his homework done, Peter went out to play. = When his homework was done, Peter went out to play. With the signal given, the train started. = After the signal was given, the train started. I wouldn’t dare go home without the job finished. = I wouldn’t dare go home because the job was not finish ed. 5. with+名词代词+动词的-ing形式 The girl hid her box without anyone knowing where it was. = The girl hid her box and no one knew where it was. Without anyone noticing, he slipped through the window. = When no one was noticing, he slipped through the window. 6. with+名词代词+动词不定式 The little boy looks sad, with so much homework to do. = The little boy looks sad because he has so much homework to do. with the window closed with the light on with a book in her hand with a cat lying in her arms with the problem solved with the new term to begin
with+复合宾语的用法 一、with的复合结构的构成 二、所谓"with的复合结构”即是"with+复合宾语”也即"with +宾语+宾语补足语” 的结构。其中的宾语一般由名词充当（有时也可由代词充当）；而宾语补足语则是根据 具体的需要由形容词，副词、介词短语，分词短语（包括现在分词和过去分词）及不定式短语充当。下面结合例句就这一结构加以具体的说明。 三、1、with +宾语+形容词作宾补 四、①He slept well with all the windows open.（82 年高考题） 上面句子中形容词open作with的宾词all the windows的补足语， ②It' s impolite to talk with your mouth full of food. 形容词短语full of food 作宾补。Don't sleep with the window ope n in win ter 2、with+宾语+副词作宾补 with Joh n away, we have got more room. He was lying in bed with all his clothes on. ③Her baby is used to sleeping with the light on.句中的on 是副词，作宾语the light 的补足语。 ④The boy can t play with his father in.句中的副词in 作宾补。 3、with+宾语+介词短语。 we sat on the grass with our backs to the wall. his wife came dow n the stairs,with her baby in her arms. They stood with their arms round each other. With tears of joy in her eyes ,she saw her daughter married. ⑤She saw a brook with red flowers and green grass on both sides. 句中介词短语on both sides 作宾语red flowersandgreen grass 的宾补， ⑥There were rows of white houses with trees in front of them.，介词短语in front of them 作宾补。 4、with+宾词+分词（短语 这一结构中作宾补用的分词有两种，一是现在分词，二是过去分词，一般来说，当分词所表 示的动作跟其前面的宾语之间存在主动关系则用现在分词，若是被动关系，则用过去分词。 ⑦In parts of Asia you must not sit with your feet pointing at another person.（高一第十课），句中用现在分词pointing at…作宾语your feet的补足语，是因它们之间存在主动关系，或者说point 这一动作是your feet发出的。 All the after noon he worked with the door locked. She sat with her head bent. She did not an swer, with her eyes still fixed on the wall. The day was bright,with a fresh breeze（微风）blowing. I won't be able to go on holiday with my mother being ill. With win ter coming on ,it is time to buy warm clothes. He soon fell asleep with the light still bur ning. ⑧From space the earth looks like ahuge water covered globe,with a few patches of land stuk ing out above the water而在下面句子中因with的宾语跟其宾补之间存在被动关系，故用过去分词作宾补：
复合材料结构设计的特点 (1) 复合材料既是一种材料又是一种结构 (2) 复合材料具有可设计性 (3) 复合材料结构设计包含材料设计 复合材料区别于传统材料的根本特点之一可设计性好（设计人员可根据所需制品对力学及其它性能的要求，对结构设计的同时对材料本身进行设计） 具体体现在两个方面1力学设计——给制品一定的强度和刚度、2功能设计——给制品除力学性能外的其他性能 复合材料力学性能的特点 (1) 各向异性性能材料弹性主方向：模量较大的一个主方向称为纵向，用字母L表示，与其垂直的另一主方向称为横向，用字母T表示。通常的各向同性材料中，表达材料弹 )和ν(泊松比)或剪切弹性模量G。 对于复合材料中的每个单层，纵向弹性模量E L、横向弹性模量E T、纵向泊松比νL (或横向泊松比νT)、面内剪切弹性模量G LT。 耦合现象：拉剪耦合与剪拉耦合、弯扭耦合与扭弯耦合 (2) 非均质性 耦合变形：层合结构复合材料在一种外力作用下，除了引起本身的基本变形外，还可能引起其他基本变形。 (3)层间强度低 在结构设计时，应尽量减小层间应力，或采取某些构造措施，以避免层间分层破坏。 研究复合材料的刚度和强度时，基本假设： (1) 假设层合板是连续的。由于连续性假设，使数学分析中的一些连续性概念、极限概念以及微积分等数学工具都能应用于力学分析中。 (2）假设单向层合板是均匀的，多向层合板是分段均匀的。 (3) 假设限于单向层合板是正交各向异性的：即认为单向层合板具有两个相互垂直的弹性对称面。 (4) 假设限于层合板是线弹性的：即认为层合板在外力作用下产生的变形与外力成正比关系，且当外力移去后，层合板能够完全恢复其原来形状。 (5) 假设层合板的变形是很小的。 上述五个基本假设，只有多向层合板的分段均匀性假设和单向层合板的正交各向异性假设，与材料力学中的均匀性假设和各向同性假设有区别。 平面应力状态与平面应变状态 平面应力状态：单元体有一对平面上的应力等于0。（σz＝0，τzx＝0，τzy ＝0） 平面应变状态（平面位移）：εz＝0（即ω＝0），τzx＝0(γ31＝0)，τzy ＝0(γ32＝0 )， σz一般不等于0。 复合材料连接方式 复合材料连接方式主要分为两大类：胶接连接与机械连接。胶接连接：受力不大的薄壁结构，尤其是复合材料结构；机械连接：连接构件较厚、受力大的结构。
with复合结构 一. with复合结构的常见形式 1.“with+名词/代词+介词短语”。 The man was walking on the street, with a book under his arm. 那人在街上走着，腋下夹着一本书。 2. “with+名词/代词+形容词”。 With the weather so close and stuffy, ten to one it’ll rain presently. 天气这么闷热，十之八九要下雨。 3. “with+名词/代词+副词”。 The square looks more beautiful than even with all the light on. 所有的灯亮起来，广场看起来更美。 4. “with+名词/代词+名词”。 He left home, with his wife a hopeless soul. 他走了，妻子十分伤心。 5. “with+名词/代词+done”。此结构过去分词和宾语是被动关系，表示动作已经完成。 With this problem solved, neomycin 1 is now in regular production. 随着这个问题的解决，新霉素一号现在已经正式产生。 6. “with+名词/代词+-ing分词”。此结构强调名词是-ing分词的动作的发出者或某动作、状态正在进行。 He felt more uneasy with the whole class staring at him. 全班同学看着他，他感到更不自然了。 7. “with+宾语+to do”。此结构中，不定式和宾语是被动关系，表示尚未发生的动作。 So in the afternoon, with nothing to do, I went on a round of the bookshops. 由于下午无事可做，我就去书店转了转。 二. with复合结构的句法功能 1. with 复合结构，在句中表状态或说明背景情况，常做伴随、方式、原因、条件等状语。With machinery to do all the work, they will soon have got in the crops. 由于所有的工作都是由机器进行，他们将很快收完庄稼。（原因状语） The boy always sleeps with his head on the arm. 这个孩子总是头枕着胳膊睡觉。（伴随状语）The soldier had him stand with his back to his father. 士兵要他背对着他父亲站着。（方式状语）With spring coming on, trees turn green. 春天到了，树变绿了。（时间状语） 2. with 复合结构可以作定语 Anyone with its eyes in his head can see it’s exactly like a rope. 任何一个头上长着眼睛的人都能看出它完全像一条绳子。 【高考链接】 1. ___two exams to worry about, I have to work really hard this weekend.（04北京） A. With B. Besides C. As for D. Because of 【解析】A。“with+宾语+不定式”作状语，表示原因。 2. It was a pity that the great writer died, ______his works unfinished. (04福建) A. for B. with C. from D.of 【解析】B。“with+宾语+过去分词”在句中作状语，表示状态。 3._____production up by 60%, the company has had another excellent year. (NMET) A. As B.For C. With D.Through 【解析】C。“with+宾语+副词”在句中作状语，表示程度。
复合材料力学 论文题目：用氧化铝填充导热和电绝缘环氧 复合材料的无缺陷石墨烯纳米片 院系班级：工程力学1302 姓名：黄义良 学号： 201314060215
用氧化铝填充导热和电绝缘环氧复合材料的无缺陷石墨烯纳米片 孙仁辉1 ，姚华1 ，张浩斌1 ，李越1 ，米耀荣2 ，于中振3 （1.北京化工大学材料科学与工程学院，有机无机复合材料国家重点实验室北京 100029;2.高级材料技术中心（CAMT ），航空航天，机械和机电工程学院J07，悉尼大学;3.北京化工大学软件物理科学与工程北京先进创新中心，北京100029） 摘要：虽然石墨烯由于其高纵横比和优异的导热性可以显着地改善聚合物的导热性，但是其导致电绝缘的严重降低，并且因此限制了其聚合物复合材料在电子和系统的热管理中的广泛应用。为了解决这个问题，电绝缘Al 2O 3用于装饰高质量（无缺陷）石墨烯纳米片（GNP ）。借助超临界二氧化碳（scCO 2），通过Al(NO 3)3 前体的快速成核和水解，然后在600℃下煅烧，在惰性GNP 表面上形成许多Al 2O 3纳米颗粒。或者，通过用缓冲溶液控制Al 2(SO 4)3 前体的成核和水解，Al 2(SO 4)3 缓慢成核并在GNP 上水解以形成氢氧化铝，然后将其转化为Al 2O 3纳米层，而不通过煅烧进行相分离。与在scCO2的帮助下的Al 2O 3@GNP 混合物相比，在缓冲溶液的帮助下制备的混合物高度有效地赋予具有优良导热性的环氧树脂，同时保持其电绝缘。具有12％质量百分比的Al 2O 3@GNP 混合物的环氧复合材料表现出1.49W /（m ·K ）的高热导率，其比纯环氧树脂高677％，表明其作为导热和电绝缘填料用于基于聚合物的功能复合材料。 关键词：聚合物复合基材料（PMCs ） 功能复合材料 电气特性 热性能 Decoration of defect-free graphene nanoplatelets with alumina for thermally conductive and electrically insulating epoxy composites Renhui Sun 1，Hua Yao 1， Hao-Bin Zhang 1，Yue Li 1，Yiu-Wing Mai 2，Zhong-Zhen Yu 3 (1.State Key Laboratory of Organic-Inorganic Composites, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China; 2.Centre for Advanced Materials Technology (CAMT), School of Aerospace, Mechanical and Mechatronic Engineering J07, The University of Sydney, Sydney, NSW 2006, Australia; 3.Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China) Abstract:Although graphene can significantly improve the thermal conductivity of polymers due to its high aspect ratio and excellent thermal conductance, it causes serious reduction in electrical insulation and thus limits the wide applications of its polymer composites in the thermal management of electronics and systems. To solve this problem, electrically insulating Al 2O 3is used to decorate high quality (defect-free) graphene nanoplatelets (GNPs). Aided by supercritical carbon dioxide (scCO 2), numerous Al 2O 3 nanoparticles are formed
With复合结构的用法小结 with结构是许多英语复合结构中最常用的一种。学好它对学好复合宾语结构、不定式复合结构、动名词复合结构和独立主格结构均能起很重要的作用。本文就此的构成、特点及用法等作一较全面阐述，以帮助同学们掌握这一重要的语法知识。 一、with结构的构成 它是由介词with或without+复合结构构成，复合结构作介词with或without的复合宾语，复合宾语中第一部分宾语由名词或代词充当，第二 部分补足语由形容词、副词、介词短语、动词不定式或分词充当，分词可以是现在分词，也可以是过去分词。With结构构成方式如下： 1. with或without-名词/代词+形容词； 2. with或without-名词/代词+副词； 3. with或without-名词/代词+介词短语； 4. with或without-名词/代词+动词不定式； 5. with或without-名词/代词+分词。 下面分别举例： 1、She came into the room，with her nose red because of cold.（with+名词+形容词，作伴随状语） 2、With the meal over ，we all went home.（with+名词+副词，作时间状语） 3、The master was walking up and down with the ruler under his arm。（with+名词+介词短语，作伴随状语。）The teacher entered the classroom with a book in his hand. 4、He lay in the dark empty house，with not a man ，woman or child to say he was kind to me.（with+名词+不定式，作伴随状语）He could not finish it without me to help him.（without+代词+不定式，作条件状语） 5、She fell asleep with the light burning.（with+名词+现在分词，作伴随状语）Without anything left in the cupboard，shewent out to get something to eat.（without+代词+过去分词，作为原因状语） 二、with结构的用法 在句子中with结构多数充当状语，表示行为方式，伴随情况、时间、原因或条件（详见上述例句）。 With结构在句中也可以作定语。例如： 1.I like eating the mooncakes with eggs. 2.From space the earth looks like a huge water-covered globe with a few patches of land sticking out above the water. 3.A little boy with two of his front teeth missing ran into the house. 三、with结构的特点 1. with结构由介词with或without+复合结构构成。复合结构中第一部分与第二部分语法上是宾语和宾语补足语关系，而在逻辑上，却具有主谓关系，也就是说，可以用第一部分作主语，第二部分作谓语，构成一个句子。例如：With him taken care of，we felt quite relieved.（欣慰）→（He was taken good care of.）She fell asleep with the light burning. →（The light was burning.）With her hair gone，there could be no use for them. →（Her hair was gone.） 2. 在with结构中，第一部分为人称代词时，则该用宾格代词。例如：He could not finish it without me to help him. 四、几点说明： 1. with结构在句子中的位置：with 结构在句中作状语，表示时间、条件、原因时一般放在
《复合材料结构设计》习题 §1 绪论 1.1 什么是复合材料？ 1.2 复合材料如何分类？ 1.3 复合材料中主要的增强材料有哪些？ 1.4 复合材料中主要的基体材料有哪些？ 1.5 纤维复合材料力学性能的特点哪些？ 1.6 复合材料结构设计有何特点？ 1.7 根据复合材料力学性能的特点在复合材料结构设计时应特别注意到哪些问题? §2 纤维、树脂的基本力学性能 2.1 玻璃纤维的主要种类及其它们的主要成分的特点是什么？ 2.2 玻璃纤维的主要制品有哪些？玻璃纤维纱和织物规格的表示单位是什么？2.3 有一玻璃纤维纱的规格为2400tex，求该纱的横截面积（取玻璃纤维的密度 为2.54g/cm3）？ 2.4 有一玻璃纤维短切毡其规格为450 g/m2，求该毡的厚度（取玻璃纤维的密 度为2.54g/cm3）？ 2.5 无碱玻璃纤维（E-glass）的拉伸弹性模量、拉伸强度及断裂伸长率的大致 值是多少？ 2.6 碳纤维T-300的拉伸弹性模量、拉伸强度及断裂伸长率的大致值是多少？密 度为多少？ 2.7 芳纶纤维（kevlar纤维）的拉伸弹性模量、拉伸强度及断裂伸长率的大致值 是多少？密度为多少？ 2.8 常用热固性树脂有哪几种？它们的拉伸弹性模量、拉伸强度的大致值是多 少？密度为多少？热变形温度值大致值多少？ 2.9 简述单向纤维复合材料抗拉弹性模量、抗拉强度的估算方法。 2.10 试比较玻璃纤维、碳纤维单向复合材料顺纤维方向拉压弹性模量和强度值，指出其特点。 2.11 简述温度、湿度、大气、腐蚀质对复合材料性能的影响。 2.12 如何确定复合材料的线膨胀系数？ 2.13已知玻璃纤维密度为ρf=2.54g/cm3，树脂密度为ρR=1.20g/cm3，采用规格 为450 g/m2的玻璃纤维短切毡制作内衬时，其树脂含量为70％，这样制作一层其GFRP的厚度为多少? 2.14 采用2400Tex的玻璃纤维（ρf=2.54g/cm3）制造管道，其树脂含量为35％ （ρR=1.20g/cm3），缠绕密度为3股/10 mm，试求缠绕层单层厚度? 2.15 试估算上题中单层板顺纤维方向和垂直纤维方向的抗拉弹性模量和抗拉强度。 2.16已知碳纤维密度为ρf=1.80g/cm3，树脂密度为ρR=1.25g/cm3，采用规格为300 g/m2的碳纤维布制作复合材料时，其树脂含量为32％，这样制作一层其CFRP的厚度为多少?其纤维体积含量为多少？ 2.17 某拉挤构件的腹板，厚度为5mm，采用±45°的玻璃纤维多轴向织物（面密
With 复合结构用法小结 “With + 复合结构”又称为“with结构”，在句中表状态或说明背景情况，常做伴随，方式，原因，条件等状语。具体结构如下： 1. With + 名词 + 介词短语? (1) He was asleep with his head on his arm. ? (2) The man came in with a whip in his hand. ? 在书面语中。上句也可以说成：The man came in, whip in hand. 2．with + 名词 + 形容词（强调名词的特性或状态）? (1)With the weather so close and stuffy, ten to one it'll rain presently.天气这么闷热，十之八九要下雨。? (2)He used to sleep with the windows open. 3. With + 名词 + 副词? (1)With John away, we've got more room. 约翰走了，我们的地方大了一些。? (2)The square looks more beautiful than ever with all the light on. 4. With + 名词 + -ed 分词（强调名词是 -ed分词动作的承受者或动作已经发生） ?(1)With this problem solved, neopenicillin 1 is now in regular production. 随着这个问题的解决，新霉素一号现在已正式生产。 ?(2)All the afternoon he worked with the door locked. 5. with + 名词 + -ing分词（强调名词是 -ing分词的动作的发出者或某动作，状态正在进行）? (1)I won’t be able to go on holiday with my mother being ill. ? (2)He felt more uneasy with the whole class staring at him. ? (3)With the field leveled and irrigation channels controlling the volume of water(水量), no such problem arose again. 6. with + 名词 + to do （不定式动作尚未发生）? (1)So in the afternoon, with nothing to do, I went on a round of the bookshops. 由于下午无事可做，我就去书店转了转。 ?(2)I can't go out with all these dishes to wash. 一、 with结构的构成 它是由介词with或without+复合结构构成，复合结构作介词with或without 的复合宾语，复合宾语中第一部分宾语由名词或代词充当，第二部分补足语由形容词、副词、介词短语、动词不定式或分词充当，分词可以是现在分词，也可以是过去分词。With结构构成方式如下： 1. with或without-名词/代词+形容词； 2. with或without-名词/代词+副词； 3. with或without-名词/代词+介词短语； 4. with或without-名词/代词 +动词不定式； 5. with或without-名词/代词 +分词。 下面分别举例： 1、 She came into the room，with her nose red because of cold.（with+名词+形容词，作伴随状语） 2、 With the meal over ， we all went home.（with+名词+副词，作时间状语） 3、The master was walking up and down with the ruler under his arm。（with+名词+介词短语，作伴随状语。） The teacher entered the classroom with a book in his hand. 4、He lay in the dark empty house，with not a man ，woman or child to say he was kind to me.（with+名词+不定式，作伴随状语） He could not finish it without me to help him.（without+代词 +不定式，作条件状语） 5、She fell asleep with the light burning.（with+名词+现在分词，作伴随状语） Without anything left in the with结构是许多英语复合结构中最
with without 引导的独立主格结构 介词with without +宾语+宾语的补足语可以构成独立主格结构，上面讨论过的独立主格结构的几种情况在此结构中都能体现。 A．with+名词代词+形容词 He doesn’t like to sleep with the windows open. 他不喜欢开着窗子睡觉。 = He doesn’t like to sleep when the windows are open. He stood in the rain, with his clothes wet. 他站在雨中，衣服湿透了。 = He stood in the rain, and his clothes were wet. 注意： 在“with+名词代词+形容词”构成的独立主格结构中，也可用已形容词化的-ing 形式或-ed形式。 With his son so disappointing，the old man felt unhappy. 由于儿子如此令人失望,老人感到很不快乐。 With his father well-known, the boy didn’t want to study. 父亲如此出名，儿子不想读书。 B．with+名词代词+副词 Our school looks even more beautiful with all the lights on. 所有的灯都打开时，我们的学校看上去更美。 = Our school looks even more beautiful if when all the lights are on. The boy was walking, with his father ahead. 父亲在前，小孩在后走着。 = The boy was walking and his father was ahead. C．with+名词代词+介词短语 He stood at the door, with a computer in his hand. 或 He stood at the door, computer in hand. 他站在门口，手里拿着一部电脑。 = He stood at the door, and a computer was in his hand. Vincent sat at the desk, with a pen in his mouth. 或 Vincent sat at the desk, pen in mouth. 文森特坐在课桌前，嘴里衔着一支笔。 = Vincent sat at the desk, and he had a pen in his mouth. D．with+名词代词+动词的-ed形式 With his homework done, Peter went out to play. 作业做好了，彼得出去玩了。 = When his homework was done, Peter went out to play. With the signal given, the train started. 信号发出了，火车开始起动了。 = After the signal was given, the train started. I wouldn’t dare go home without the job finished. 工作还没完成，我不敢回家。 = I wouldn’t dare go home because the job was not finished.