作业帮 > 英语 > 作业

when while

来源:学生作业帮 编辑:作业帮 分类:英语作业 时间:2024/05/17 10:21:13
when和while的用法分别是什么
解题思路: 如下
解题过程:
1.when 是指某个时间所发生的事,用于在完成时态 while是指某个时间段所发生的事,用于进行时态 2.①when意为"在……时刻或时期",它可兼指"时间点"与"时间段",所引导的从句的动词既可以是终止性动词,也可是持续性动词。如: When I got home, he was having supper.我到家时,他正在吃饭。 When I was young, I liked dancing.我年轻时喜欢跳舞。 ②while只指"时间段",不指"时间点",从句的动词只限于持续性动词。如: While I slept, a thief broke in.在我睡觉时,盗贼闯了进来。 ③when从句动词为终止性动词时,不能由while替换。如: When he came yesterday, we were playing basketball.昨天他来时,我们正在打篮球。 ④当从句的谓语是表动作的延续性动词时,when, while才有可能互相替代。如: While / When we were still laughing, the teacher came in.正当我们仍在大声嬉笑时,老师进来了。 ⑤当从句的谓语动词是终止性动词,而且主句的谓语动词也是终止性动词时,when可和as通用,而且用as比用when在时间上更为紧凑,有"正当这时"的含义。如: He came just as (or when) I reached the door.我刚到门那儿,他就来了。 ⑥从句的谓语动词如表示状态时,通常用while。如: We must strike while the iron is hot.我们应该趁热打铁。 ⑦while和when都可以用作并列连词。 Mike is tall while his brother is short.迈克的个子很高,然而他弟弟很矮。 Mary was on her way home when two big boys stopped her.玛丽正走在回家的路上,这时两个大个子男孩拦住她
最终答案:略