完成句子，根据中文提示，完成句子。
I think that Yang Liwei and Liu Xiang are both our country’s _______ (英雄).
We should exercise to _______ us _______ (增强体质).
Driving carelessly _______ (引起) accidents.
The rivers in the countryside are much _______ (清澈) than those in the cities.
Beijing Opera              (充满) famous stories ,beautiful facial paitings, wonderful gestures and fighting.