—Do you think playing cards is beneficial to our study?—No，if ________，it can help us kill time when we have nothing to do.

Everyone doesn’t agree to the plan. Some support it while I’m one of ______ opposed to it.

Mr. Smith doesn’t like all that empty talk between Susan and Joan, which he thinks will definitely get them ________.

I’d like to buy a present for my father’s birthday, ________at a proper price but of great use.

________ is mentioned above that the number of the students in senior high school is increasing.