（2）They produced 15 % more rice last year than they did in 1990.
去年他们的水稻产量比1990年的产量增加了百分之十五。
注意：以上可归纳为句型：“A is … times + adj. / adv. (比较级)+ than B.”
另外这一句型还可转化为句型“A is … times as + adj. / (原级)+as B.”例如：
（1）At least, the train runs 6 times as fast as the boat.
火车的速度至少为小船速度的六倍。
（2）After the experiment, the plant is four times as tall as it was before.
在实验以后，这种植物为过去高度的四倍。
Grammar教学建议
Before class ask Ss to sum up the use of –ing Form and in class the teacher may have a contest among Ss who have been divided into two or several groups to see which group has done the job best. In this way Ss will usually have a good preparation of their work and will be willing to do what seems boring to them, which is the necessity to learn well. The teacher may add what has been left out and have a summary. After that, enough exercises are needed to help Ss to use, understand, remember and master what they have learned. Only through the use of the language can Ss really get what they are required to get.
Grammar-- -ing Form
Revising the use of –ing forms of the verbs and make Ss grasp the use of it.
I. v+ing 的句法功能：
1.作主语。可直接作主语， 表示一般抽象概念时，可以与不定式互换，但在句型“It is no use/good”等候一般用动名词。
e.g. It is no good smoking too much.
Seeing is believing.
2. 作宾语。有些动词可以直接跟v.-ing作宾语，
如：mind, miss, enjoy, escape, prevent, practice, postpone, suffer, suggest, keep(on), avoid, admit, bear, deny, advise, delay, risk, resist, finish, fancy, excuse, imagine, consider, can’t help,
下列 “vi.+介词或副词” 构成的短语动词，后接v.-ing作宾语。
succeed in, approve of, persevere in, inquire of, persist in, complain of, insist on, aim at, benefit from, burst out, can not help, be busy (in), be on the point of, feel like, guard against, give up, go on , keep on, leave off, put off , be used to, object to, be accustomed to, refer to, be opposed to, stick to, be dedicated to, be devoted to ,look forward to, turn to, come near to, devote oneself to, due to, pay attention to, be faithful to ,be equal to, be familiar to, be sentenced to…
e.g. We enjoy learning English.
He insisted on seeing the exhibition.
I am looking forward to seeing you.
The mayor considered building a new town-hall.
3. 作表语。作表语表示主语的内容或表示状态，说明主语的特点（ 这是主语是v.-ing形式的执行者）。
e.g. Our aim is studying English well.
His speech is very exciting.
4. 作定语。 表示主动，相当于一个定语从句， 表示动作在进行；或说明用途或作用。(单个一词作定语，须放在所修饰词的前面；短语作定语须放在所修饰词的后面)
e.g. The lady talking (who is talking) with him is a doctor.
Will the swimming pool be open?
The man walking by the lake is a scientist.
5. 作补语。作宾语有两个特征：一是宾语与 v.– ing 有主谓关系,且宾语是v+ing动作的执行者；二是v.+-ing形式所表示的动作正在进行。
union3 Australia教学目标