...ing, people came up with an idea to build an artificial wall that imitated the surface of a real mountain and on which most of our competitions are held now.
I know whereof I speak. I know whereof I talk about. 老师好！这里的whereof=of which/what,那第一句话为什么不在speak后面加about？whereof中的of跟在主句动词后还是从句动词后？whereof的词性是连词还是副词？像这种where/there/here+介词构成的合成词...
So long as Ben is shown exactly how to do something, he is less likely to figure out himself how to accomplish such a task.如果我们向Ben演示该如何做某件事，那他就不大可能自行想方设法完成这件事。 请问专家老师们，as long as或so long as的意思通常是...
...配中是不是必须要用不定冠词？
He has a good knowledge of mathematics. 他的数学(知识)很好。
He has a wide knowledge of history. 他有广泛的历史知识。
It is necessary to have a good knowledge of the essentials of English grammar. 了解英语语法的一些要素...
1. 引导定语从句的是关系代词，如：
The girl who is behind youis my daughter.
因为 who 在从句中充当了主语所以叫关系代词。
2. 引导宾语从句的叫连接代词，如：
I don't know what you name is.
可是这个 what 也充当了从句...
... of 500 taxis navigated by computers, often with
no safety drivers in them for backup1. a fleet of 500 taxis 中a
fleet of 是限定词吗？类似于a lot of？还是说中心词就是fleet?2. with是否表示伴随，还是有其他含义?3. in them成分分析（定状补）?4. for backup成分...
Do you want another cake ?No, thank you. ( )A. I still have got some leftB. I've still got some leftC. I still have some onesD. I have still some ones对这道题，我有2个疑问：1）题目中的cake是可数还是不可数？词典释义cake既可数（蛋糕；饼状食物；饼）...
...lved in many extra-curricular activities. 她参加了许多课外活动。The
school offers a variety of extracurricular activities. 这所学校有各种各样的课外活动。There
are clubs and other extracurricular activities at the school. 该校有俱乐部和其他课外活动。As
well as ...
This jumping to our children's defence is part of what fuels the "walking on eggshells" feeling that surrounds our dealing with other people's children.