A swallow flew west skimming the lake 在这句中：flew 是过去式,为什么 skim用分词形式?

A swallow flew west skimming the lake 在这句中：flew 是过去式,为什么 skim用分词形式? Three geese in a flock.One flew east one flew west,one flew cuckoo's nest..是谚语么? Swallow Swallow flew one swallow does not make a summer _______the plane.A.Flew down B.Down flew C.Down was flying D.Down flew one swallow does not make a summer中文翻译? one swallow doesn't make a summer是一个谚语。 翻译Truth is a hard pill to swallow. A rock flew through the air West West West gloryhole swallow swallow是什么意思 swallow是什么意思 Two girls were flew a kite.为什么flew用错了