人教版八年级英语上Units7-9单元同步常见考点失误解析与自我检测
Unit 7 Will people have robots?
1.半小时后他们将到达这儿。
误：They will arrive here after half an hour.
正：They will arrive here after half an hour.
解析： 介词after与 in都可以接一段时间，after于过去时的句子中，表示“在多长时间以后”。如：
He came back after ten days.
他10天后回来了.
The old man left home in 1924 and came home after thirty years.
那老人1924年离开家.30年后才回来.
in常用于含将来概念的句子中，意思是“在多长时间以后”或“在多长时间以内”。如：
He will come back in ten days.
他将在十天后回来.
He said he would come back in ten days.
他说他将在10天后回来.
注意：“in+段时间”也可用于过去时。意思是“在......内”。如：
He wrote the book in two and a half years.他是在两年半的时间里写完这本书的.
注意:如果after后接的不是段时间，而是点时间,则可用于将来时。如:
My brother will go there after four o'clock.
我兄弟四点钟后去那儿.
He will leave after New Year's Day.
过了元旦他就要走.
[课文要点] Will people use money in 100 years? (P49)
2. 他小时候学会了骑自行车。
误：He learned to ride a bike during he was a child.
正：He learned to ride a bike when he was a child.
解析介词during表示“在……的期间”，后面跟“特指的一段时间”，不可以接从句。如：
What are you going to do during the winter vocation?
你打算在寒假期间干什么？
During the winter we play football.
冬季我们踢足球。
[课文要点] During the week, I’ll wear smart clothes. (P55)
3. 去年我们在这儿盖了几百栋新楼房。
误：We built hundred of new buildings last year.
正：We built hundreds of new buildings last year.
解析：当hundred，thousand，million和billion 表示不具体的数目时，用复数形式，须跟介词of 连用。如:
Hundreds of people come to visit this museum every day.
每天有成百上千的人来参观这个博物馆。
注意：如果这些词前面有基数词修饰，表示具体数字时，则不用复数形式。如：
There are more than two thousand teachers and students in our school.
我们学校有两千多名师生。
[课文要点] However, they agree it may take hundreds of years. (P53)
4. 桌上有两张纸。
误：There are two papers on the desk.
正：There are two pieces of paper on the desk.
解析paper表示“纸”，是物质名词，没有复数形式。“一张纸”用a piece of paper，“两张纸”用 two pieces of paper。如：
Could you please give me a piece of paper, please?
请递给我一张纸好吗？
We will use less paper in the future.
将来我们会使用更少的纸。
[课文要点] Books will only be on computers, not on paper. (P49)