1. average n. 一般水平；平均数 a. 平均的；一般的 v. 平均为，均分
He is about average in his lessons. 他学习一般。
The average age of the boys in this class is fifteen. 这个班男孩平均年龄是15岁。
The airport averages about a thousand flights a month.
这个机场的吞吐量平均为每月1 000架次。
The cost of lunch averaged one dollar a week. 午餐费用平均每周1美元。
2. period n. 时期，（一段）时间
There were long periods when we had no news of him.
很长时间我们都没有他的消息。
His teenage son is going through a difficult period at the moment.
他的十几岁的孩子正经历着困难的时期。
3. assume vt. 假定，设想
I assume that you have heard the news. 谅必你已听到了消息。
He assumed the report to be valid. 他猜想那报告是有根据的。
4. capacity n. 能力，才能 ; 容量，容积
This book is beyond the capacity of young readers. 这本书非少年读者所能理解。
The intellectual capacity and passion of teachers shows no boundaries.
教师们的智力能力和工作热情都是无界的。
Her capacity to remember facts is remarkable. 她具有非凡的记忆力。
His total lung capacity is twice the size of an average person.
他的肺活量是正常人的2倍。
The stadium has a seating capacity of 18 000. 这个体育场能容纳18 000名观众。
5. physical a. 身体的，肉体的；物质的；物理的
She showed great sympathy for those with mental or physical disabilities.
她非常同情那些有精神或生理残疾的人。
Scientific researches have helped people to get a glimpse of the physical world.
科学研究使人们对物质世界有了一些认识。
He chose the course of physical chemistry.他选了物理化学课。
6. particular a. 特殊的，特别的；特定的，某一的
She has a particular preference for Chinese art. 她对中国艺术有特别的爱好。
We will make an exception in this particular case. 我们将把这个例子当作例外。
7. constant a. 经常的，不断的
We live in a world of constant change, and we need to understand it.
人们生活的世界处于持续不断的变化中，我们也有必要理解这种变化。
He was constant in his efforts to improve his skills.
他为提高技能做了不懈的努力。
8. sensitive a. 敏感的（to）；灵敏的
We need to be more sensitive to the needs of the young students.
我们对青年学生的需求应更敏感。
Don’t be so sensitive; I was only joking. 别太敏感，我不过开了个玩笑。
He’s very sensitive about his ugly appearance. 他对自己丑陋的外貌很敏感。
9. serve v. 满足，符合； 服务，招待
We don’t get enough aid to serve our needs.
我们得不到足够的援助来满足我们的需要。
Oh, please don’t serve me first. I can wait. 噢，不要先招待我，我可以等。
First come, first served 先到先招待
Phrases and Expressions
1. on (the) average 平均起来，一般说来
On average we receive 5 letters each day. 我们平均每天收到5封信。
These youths are on the average better educated than those already in the marketplace.
一般说来这些年轻人要比早已工作了的人接受了更良好的教育。
2. be likely to 可能
Are you likely to be in London this summer? 今年夏天你会在伦敦吗？
An accident is likely to happoen at that intersection.
那个十字路口很容易发生交通事故。
These old buildings are very likely to be knocked down in a year or two.
这些老房子在一两年之内会被拆除。
3. bring about: to make sth. happen 引起，实现，造成
She made various efforts to bring about a peaceful solution to the problem.
她做了各种努力以期和平解决这个问题。
That unpopular measure finally brought about the downfall of the government.
那项不得人心的措施最终导致了政府的垮台。
The economic reform brought about great changes in the lives of the common people.
经济改革在老百姓生活方面带来了巨大变化。
4. in particular: especially 特别是，特别地
You should avoid eating fatty meat, pork in particular.
你应当避免吃肥肉，尤其是猪肉。
I had several plans, and one in particular seemed good and feasible.
我有几个计划，其中一个看起来不错
5. tend to 趋向；往往会
Other studies suggest that people who pay with credit card spend more and tend to forget how much they spent.
另外的一些研究表明用信用卡付款的人花钱多，而且往往忘记他们花了多少。
Many children tend to sit in front of TV for a whole day if they can.
如果可以的话，很多孩子往往会在电视机前坐一整天。
Otherwise, such courses may tend to become boring. 否则的话这样的课程会变得很枯燥。
6. serve/answer a/the purpose 达到……目的，起……作用
This pan is not the best one, but it will serve the purpose.
这个平底锅并不是最好的，但足可以用的了。
We can’t see that it would serve any purpose. 看不出它会有什么作用。
7. serve/answer a/the purpose 达到……目的，起……作用
This pan is not the best one, but it will serve the purpose.
这个平底锅并不是最好的，但足可以用的了。
We can’t see that it would serve any purpose. 看不出它会有什么作用。
