1.The boys went【 】（上上下下）the stone steps.
2.他有时会讲笑话.
He sometimes 【 】【 】
3.尽管他有10个孩子,但是她独居.
Although she has ten children,she lives【 】【 】
4.合并为一句：
——Don't play with matches!my mother told me.
My mother told me【 】【 】 【 】with matches.
——Tom can't throw donuts to the panda.I think.
I 【 】【 】Tom【 】【 】donuts to the panda.