1.be doing sth.when
e.g.We were having a meeting when someone broke in.
2.be about to do sth.when
e.g.We were about to set off on our way whenit suddenly began to rain.
3.be on the point of doing when
e.g.She was on the point of going to shop when the telephong rang.
4.had done sth.when
e.g.He had just finished his home work when someone asked him to play basketball.
5.hardly...when(若hardly放句首要倒装,且倒装为主倒从不倒.因为hardly为表否定意义的副词,该类型的词,放句首要倒装）
e.g.Hardly had I arrived when the train left.
(亲,我打这些字可累了,又换中英文,又改大小写的） 1.be doing sth.when
e.g.We were having a meeting when someone broke in.
2.be about to do sth.when
e.g.We were about to set off on our way whenit suddenly began to rain.
3.be on the point of doing when
e.g.She was on the point of going to shop when the telephong rang.
4.had done sth.when
e.g.He had just finished his home work when someone asked him to play basketball.
5.hardly...when(若hardly放句首要倒装,且倒装为主倒从不倒.因为hardly为表否定意义的副词,该类型的词,放句首要倒装）
e.g.Hardly had I arrived when the train left.
(亲,我打这些字可累了,又换中英文,又改大小写的）