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1、Unit3重点知识及练习表示表示过去过去某个时刻某个时刻正在进行正在进行的动作。的动作。1.结构：结构：(1)肯定句肯定句 :主语主语+was/were+ doing(2)否定句否定句:主语主语+was/were+not + doing(3)一般疑问句：一般疑问句：Was/Were +主语主语+doing ?肯定回答肯定回答 ：Yes ,主语主语 was/were .否定回答：否定回答：No, 主语主语 wasnt/werent.如：如：Were you studaying at that time ?Yes , I was . No , I werent.一、过去进行时一、过去进行时2.标志
2、词有标志词有:(1)at +时刻时刻+过去的时间过去的时间 如：如：I was watching TV at eight oclock last night. He was having a math class at this time yesterday morning. (2) from +时刻时刻 to + 时刻时刻 + 过去的时间过去的时间如：如：We were having classes from three to five yesterday afternoon.(3) at that time 在那时在那时 如：如：She was playing computer games
3、 at that time. （4）. （主句）过去进行时when （从句 ）用一般过去时（短暂性动词）用过去进行时(延续性动词)如： I was doing my homework when you came to school.(come是短暂性动词) I was speaking English when you were writing .(write是延续性动词)（5）.(主句)过去进行时while(从句) 用过去进行时.如：I was speaking English while you were writing还可以这样写上面两种结构：When/while (从句)放在前面，用“，”与主句隔开.如When you came to school， I was doing my homework . While you were writing, I was speaking English