In his lecture, the professor referred to the belief, in contrast to all other countries, ______the elderly are wise, ______is particularly dominant in the Chinese culture．

This problem is too difficult. — You can’t work out the math problem unless you ______ to your teacher carefully. [ ]

What’s your sister drinking at the moment ?

Is Jim coming by train? —I’m not sure. He _________ drive his car.

How long can I have your dictionary?— it till next term.