the kids ___on the playground when the alien landed 说明一下为什么不

the kids ___on the playground when the alien landed 说明一下为什么不 翻译：I was watching TV when the alien landed . I( )TV when the UFO landed The girl was shopping when she saw the alien get out.中get为什么 The boy was seen ___on the playground.A.play B.to play C.pla When the alien （ ）（come） out of the restaurant mary was shopping when the alien entered the supermaket 选择题详细说明为什么The astronauts landed on the earth ______the morin The boy___ down the street when he UFO landed When Christopher Columbus landed in the New World,the Nort Most kids like do some a_____ on the playground. 1 -what was he doing when the UFO landed?