(2)reduction n. 降低；减少

　　①Speaking of pollution, we really need to reduce the use of cars.

　　说到污染，我们真的需要减少汽车的使用。

　　②She reduced her weight 50kg while he only reduced his weight 4 kg.

　　她把体重减少到50千克，而他的体重仅减少了4千克。

　　【答案】　②to；by

　　 (教材P12)I'm 19 years old and I used to be a drug addict. 我19岁，曾经是个瘾君子。

　　(1)used to 　过去常常

　　(1)There used to be... 过去常常有......

　　(2) be/get used to (doing) sth. 习惯(做)某事

　　be used to do sth. 被用来做......

　　①I used to get up at 6 o'clock when I was at school.

　　我上学时经常6点起床。

　　②There used to be a cinema here.

　　从前这里有一家电影院。

　　③He used (stay)up late，but now he is used to (go)to bed early.

　　他以前总是熬夜到很晚，但是现在已经习惯早睡了。

　　④This kind of wood can be used (make) into tables.

　　这种木材可以用来做桌子。

　　【答案】　③to stay；going　④to make

　　[语境助记]　

　　I used to play football on the playground, but now I am used to reading in the library and the knowledge I get can be used to equip myself.

我过去常常在操场上踢足球，但现在我习惯在图书馆里看书，我获取的知