Tom, clean up the broken glass _________ someone walks on it.
---Does the young man standing at the gate ______ the car? --- No. The car is _________ his father.
His parents are convinced ____ the fact the their son always focuses his mind ___ his study.
The farmers built long fences, ____ keeping the wild dogs out of them.
Mr Smith ______ a book about China last year but I don’t know whether he has finished it.
_____ I read the story, I’m greatly moved by it.