现在完成时
基本结构:主语+have/has+过去分词(done)
①肯定句:主语+have/has+过去分词+其他
②否定句:主语+have/has+not+过去分词+其他
③一般疑问句:Have/Has+主语+过去分词+其他
④特殊疑问句:特殊疑问词+一般疑问句(have/has+主语+过去分词+其他\
He has worked for us for ten years.
Has he worked for us for ten years. 过去完成时
基本结构:主语+had+过去分词(done)
①肯定句:主语+had+过去分词+其他
②否定句:主语+had+not+过去分词+其他
③一般疑问句:Had+主语+过去分词+其他
肯定回答:Yes,主语+had
否定回答:No,主语+hadn't
④特殊疑问句:特殊疑问词+一般疑问句(had+主语+过去分词+其他)
语法判定:
( 1 ) by + 过去的时间点。如:
I had finished reading the novel by nine o'clock last night.
( 2 ) by the end of + 过去的时间点。如:
We had learnt over two thousand English words by the end of last term.
( 3 ) before + 过去的时间点。如:
They had planted six hundred trees before last Wednesday.