i saw a plane coming from the east 这个算什么时态 不是从句的一句话 也可以有两个时态么

I saw __ plane coming from the east.这个空填的是a,为什么the不行? I saw the plane coming toward me.I dashed for cover这句话是什么意思啊. I saw the plane coming towards me .I dashed for cover用on连接句子 i saw a plane coming from the east 这个算什么时态 不是从句的一句话 也可以有两个时态么 （On) I saw the plane coming towards me.I dashed for cover.On seeing the plane coming towards me.（On) I saw the plane coming towards me.I dashed for cover.连接句子.On seeing the plane coming towards me.为什么不用 On sawing? （On) I saw the plane coming towards me.I dashed for cover.连接句子并说明理由. 请高手翻译此句,谢谢：When I saw the plane coming towards me, I dashed for cover 用括号里面的词来连接句子,(on) I saw the plane coming towards me .I dashed for cover. i saw a saw saw a saw. I saw the plane coming towards me.I dashed for cover.翻译!再说下dash和cover在这的中文意思! I saw the plane coming towards me.I dashed for cover.这是NCE Book 2 P.90 上的句子 把i saw the plane coming towards me.和i dashed for cover.两句话用on连接需要时可以对原句进行必要的改动.. I saw the train______into the station slowly a minute ago A.comes B.is coming C.to come D.coming I saw a plane __________(fly)over the building just now . I saw a thief coming into the house.改为被动语态 i saw a saw saw a I never saw a saw saw a I saw a saw swa a saw.