that不能省略的情况:
4. 用it作形式宾语的宾从,后面的that不可省略。
1. 接复合宾语的句子中,为保持句子平衡, 用it作形式宾语, 将真正的宾语后置。 (即:主语+谓语+it +宾补+that从句)。 常接复合宾语的动词有: consider, make, find, see, hear, feel, believe, think ...
宾从的虚拟语气
2. 主句谓语动词为以下单词和词意时,宾从谓语必须用(should)+do
一坚持 二命令 三建议 四要求 外加一敦促
insist
advise, suggest, propose demand, require, request, ask
urge
The teacher ordered that the homework (should) be handed in on time. My mother suggests that we (should) eat out for a change this weekend. 注意;当suggest 作“表明,暗示”讲时,不用虚拟语气;
3. 连接词:从属连词that, whether, if 连接代词who, whom, whose, which, what, whoever… 连接副词where, how, why, when
Jack told me _____t_h_a_t ____he had been there twice. 杰克告诉我他去过那里两次。 Tom asked me ___if_/_w__h_e_th_e_r___I was a student. 汤姆问我是不是学生。 Do you know __w__h_o_(_w_h_o_m__)__they are waiting for? 你知道他们在等谁吗?