A）根据括号中所给的汉语写出单词，使句子意思完整正确。

小题1:One of the secrets of our success is to believe in    ▲  （我们）.

小题2:Frank loves playing basketball and practises    ▲   (两次) a week.

小题3:Do you know the difference    ▲   (在…..之间)”beside” and “besides”.

小题4:We are very    ▲   (自豪) that a pupil from our school has won the prize.

小题5:Paper making is one of the greatest    ▲  （发明）in world history.

小题6:The day before yesterday he came back and    ▲   (度过) the weekend with his parents.

根据下图的溶解度曲线回答下列问题：

（1）60℃时__________物质的溶解度最大。

（2）升高温度可使________物质的不饱和溶液变为饱和溶液。

（3）M点表示______________________________。

（4）当A中混有少量B时，可用__________法提纯A。