【知识点详解】
这篇内容主要涉及的是九年级英语学习，主题为"The world has changed for the better"，即“世界变得更好了”。以下是对相关知识点的详细解释：
**词汇部分：**
1. "过着……的生活"对应的英文是"live a ... life"。例如：Most people lived a hard life in the past in China.
2. "上百万人"可以翻译为"millions of"。例如：Millions of children have received a better education because of Project Hope.
3. "吸毒"是"take drugs"，"违反规则"是"break the rules"。例如：We mustn't take drugs or break the rules.
4. "提供"在英语中是"provide"，"给我们提供"是"provide us with"。例如：Our parents provide us with comfortable conditions.
5. "习惯散步"用英语表示为"be used to taking a walk"。例如：My grandpa is used to taking a walk after supper every day.
6. "选定"是"choose"。例如：After the meeting, they chose the best way to solve the problem.
7. "成功地做某事"是"succeed in doing sth."。例如：The doctor has been successful in saving the patient.
**词汇分类：**
**合成法的单词：**
- Downstairs (楼下)
- Policeman (警察)
- Hometown (家乡)
- Fireplace (壁炉)
- Grandson (孙子)
**派生法的单词：**
- Laborer (工人)
- Impolite (不礼貌的)
- Peaceful (和平的)
- Unfair (不公平的)
- Dislike (不喜欢)
- Exciting (令人兴奋的)
- Housewife (家庭主妇)
**填空练习：**
1. 我妈妈不去上班。她是个家庭主妇。She's a housewife.
2. 根据一个人的衣服来判断他是不公平的。It's unfair to judge a person by his clothes.
3. 我们应该结束战争，让所有人都能生活在一个和平的世界。We should end the war and let all the people live in a peaceful world.
4. 我奶奶摔倒了，伤到了腿。My grandma fell downstairs and hurt her legs.
5. 这个残忍的老板让许多小孩为他工作。This cruel boss let many child laborers work for him.
6. 托马斯·爱迪生一生中有1093项发明。Thomas Edison had 1093 inventions in his life.
7. 在美国，吃饭时大声说话是不礼貌的。It's impolite to speak loudly during the dinner in America.
**语法与句型：**
(A) 使用 have been(to), have gone(to), have been in (at) 的区别：
1. have gone to 表示已经去了某地但未回来，例如：Where's your father? He has gone to Beijing on business.
2. have been to 表示去过某地已回来，例如：Tom and Mary have been there twice.
3. have been in 表示在某地待了一段时间，例如：My parents have been in Fuzhou since they got married.
4. have been at 用于较小的地方，例如：I have been at this school for about 10 years.
(B) 由 how long, for, since 引导的时间状语中，句子动词通常使用延续性动词。对应延续性动词如下：
- buy -> have had
- borrow -> have kept
- leave -> have been away from
- die -> have been dead
- finish -> have finished
- begin -> have started
- begin to do -> have started to do
- join -> have been a member of
- become -> have become
- arrive/get to/reach -> have been in/at/for
- close -> have been closed
- open -> have been open
将句子改为现在完成时：
1. 他1998年参军。他已经参军23年了。He has been in the army for 23 years. (假设当前年份为2021年)
