Then moment _________ Mary will always remember is _________ Mr. Black gave her a lot of valuable advice on how to improve her writing.
Having a walk after supper is certainly good for the old people, but it remains ______ whether they will enjoy it.
If better use is _______ your spare time, you will have a more brilliant future.
The fire made _____ difficult to rescue the people trapped under the ruins in the earthquake.
The world will be different, and we will have to be prepared to ________ the change.
You were silly __________ your car, otherwise it wouldn’t have been stolen.