- It seems to me traveling by plane is dangerous.- I don’t think so. ______ planes have the best safety records.
Four days __________ enough for us. We still need ________ two days.
The big fire hasn’t been __________ yet?
We will never forget those happiest days _______ we spent on the summer camp.
We wondered __________ this afternoon.
The little boy was last seen __________ football by the river.