Do you mind my joining your discussion — ______ You are so welcomed.

sor White has written some short stories, but he is________known for his plays.

I’m sorry I______ my exercise book at home.—-Don’t forget ______it to school tomorrow， please.

It is reported that large amounts of locusts(蝗虫) _____ in their activity in the north now.

_________your watch five minutes ahead is an effectiveway to avoid being late.