Excuse me, could you tell me __________?—In ten minutes.

These Maths problems are too hard to ______. Can you help me?—There are many ways, but the most important is to try your best.

Ann is a careful girl．She always goes over her exercises to ____ here are no mistakes．

Many students ______ changes to show themselves in class because the class size is too big.

The girl is doinghomework.