英语语法 非谓语动词...
有一点我老是搞不清楚.有时用过去分词,有时过去分词前还加个having...比如
( )all my letters,I had a drink and went out.
A Finished B Having finished
The birds,( )by the presence of the children,disappeared quickly.
A frightened B having been frightened
( )her husband was badly hurt,she burst into tears.
A Hearing B Having heard
要怎么区别判断呢?结合例子说明下吧~
P.S.错综条件句怎么用?
希望说明尽量简短易懂,避免冗长.