Only after he had spent several nights working on the math problemto wonder whether the problem was wrongly set.[ ]

Have you got any news from Jane about the English contest？— No She said she ______ know when ______ be held, either

Perce Blackborow and his companions stayed on Elephant Island for six months before rescue came, so they ________ a lot of difficulties.

Miss Yuan, you promised!— Well, ____________. But it was you broke your word first.

It’s time you changed your attitude ___ your studies, for the time is running out