1 when和 while
was/ wreredoing
when...
be about to do sth when...
had done sth
when... 这是when比较特殊的考点,表并列,这时,突然的意思
while 有虽然(句首),但是(居中)
Mary always does housework at home, while her husband plays Majong outside.
做 当。。。讲的时候,while后用延续动词 when后也可短暂动词时态不是看这两个词的,时是时间,一看时间...