It is difficult to       between Mary and her younger sister

You have done so much that you are       pass the exam．

Tony      the fact that he had made a mistake．

He felt happy when his boss stated that he could     some time for exercise．

           when Newton was sitting under an apple tree.

We can’t accurately    what will happen next.   

—Which sport is the most popular in the US?
—It’s hard to say．It largely ______ what you mean by “popular”?

Mr．Wang ______ the person referred to at the meeting be put in prison．

With so many problems __________, the new mayor will have a hard time in his poor town.

The soil that had been converted to ____ flowers was on its way ______ .