Until的用法

What's the matter?的同意句：What's wrong?

Until的意思，用它举几个句子:
直到...(意思)
例句:I didn't go to bed until my father came back.
I could see nothing until I opened the lights.
I knew nothing about the accident until Li Lei told me.
Until 多用于一般过去式的句子中，until后接从句。

What happened to Michael?意思是Michael怎么了？
或者是Michael出什么事了？

fall 构成的几个短语：
fall down 掉下（The toddler tried to walk but kept falling down.那小孩学着走路但老是跌跤．）
fall off 从..掉下（He fell off the bike and broke his right leg.他从自行车上摔下来，摔断了右腿
）
fall behind 落后（The major world power are afraid of falling behind in the arm race.世界各大强国均惟恐在军备竞赛中落后。）
fall （fast）asleep （很快）睡着（He was so tired that he fall fast asleep in his room.他太累以至于很快就在他的房间里睡着了)
fall back 撤退（The emery fell back as our troops advanced.我军前进，敌军后退。）

lie的现在分词，和别的意思:
以下两种意思的现在分词都是lying
躺lie——lay——lain ：He was lying on th