英文句子問題

11.This exercise_____ (do) by yourself.
12.The girl______ (lie) on the floor an hour ago.
13.He_____ (do) the work already.
14.The moon and the stars____ (shine) at night.
15.What____ (be) the matter?
16.As soon as he _______ (finish) the letter, he_____ (put) down his pen.
17.She ________ (finish) like a fish last summer, but she______ (be) afraid of water now.
18.I_______ (meet) John when I _____(go) to school yesterday.
19.Dogs always _____ (bark) at strangers.