句型转换

1. You must practice speaking more English.

    You     _ _          practice speaking more English.

2. Lucy is as tall as my sister.

    Lucy is                  height (高度) __     my sister.

3. Tom likes swimming, and Jim likes skating.

    Tom's hobby                            Jim.

4. The boy had quitted learning the piano.

    The boy had _                           _the piano.

5. Williams had interest in the space science very much.

    Williams was                                 the space science.

实验室要配制1mol•L^-1的稀硫酸250mL，回答下列问题：

（1）需要98%密度为1.84g/cm³的浓硫酸______mL

（2）配制时，该实验两次用到玻璃棒，其作用分别是______、______．

（3）配制过程中出现以下情况，对所配溶液浓度有何影响（填“偏高”“偏低”“不影响”）

①没有洗涤烧杯和玻璃棒．______．

②如果加水超过了刻度线，取出水使液面恰好到刻度线．______．

③容量瓶没有干燥．______

④定容时俯视容量瓶瓶颈刻度线______．