rld’s elderly population will exceed ____ of children by 2060,when each group ____ toaccount for about one fifth of the population.

A lot of water _______ in Xian every year. It’s a big problem.

He cut down a tree with a axe.[ ]

Why not listen to BBC news to improve your listening skills— It’s difficult for me follow.

下列各句中，没有语病的一项是