问题 It's + adj/n + doing 或 to do 的逻辑原理？

It's important to learn foreign languages.为什么不能说learning?It's foolish behaving like that.为什么不能说to behave?It's fun to do/doing - 为什么 doing和to do又都可以？It's of no use crying/to cry - 为什么二者均可？在It is adj/n +...这种结构中，...

问题 it must have been 和 it must be的区别

如这个句子所言，如果这里是 it must be Tom 的话行不行呢？

问题 it's easy to make friends you are rich是什么结构

书上看到一句话 it's easy to make friends you are rich,but a friend in need is a friend indeed.it's easy to make friends you are rich是什么结构，you are rich是定语吗？定语不是只能修饰名词么，看它在这句话里不像是修饰friends的，但是定语可以修饰整...

问题 句子分析

Planning is key to any business throughout its existence. Every successful business regularly reviews its business plan to ensure it continues to meet its needs.疑问：ensure it这里的it指的是business plan，那么meet its needs这里的its指的是successful business，...

问题 一个复杂句子中at的用法问题

And even though most of the decisions at what is effectively Asia's largest political pantomime are pre-determined, it's still worth having a think about some of the big economic priorities forChina's leaders.请问：(1) decisions 后为什么用 at？(2) at what is effectively Asia'...

问题 be used 和 have been used的区别

Six million hand driven rivets and 53,000 tonnes of steel were used in its construction. 这里面填的were  used 和 have been used 有什么区别呢？ 一个是强调过去的事实 ，一个是和现在还有关注，或者对现在还有影响？ 求指点！

问题 as much...than的用法正确吗

... the Spitfire – aviation in the 1930s really did sprint forward in leaps and bounds.这句话中Hurricane和Spitfire均是一种型号的飞机。句中as much怎么会和than搭配？是否应该改为much more才正确？希望老师解惑，谢谢! 

问题 句子结构分析（happy前为什么没有is）

...s freed some memory（内存） for running processes（运行的进程） and the OS（操作系统） to use.请教各位专家，“happy that”从句是做什么句子成分呢？happy前的be动词为什么可以省略呢？

问题 What it looks like与how it looks like

What it looks likebe like是哪个词？how的与之相关的用法是什么？

问题 it指代什么

experiment it prepares中，it指代什么？it prepares放在整句话怎么翻译？

问题 it指什么

It makes it so much easier to split the bill when we eat out想请教一下，make it 的 it 是指 to split the bill 嘛？还是指to split the bill when we eat out？

问题 新概念英语第二册第86课自己两处疑问

... speedboat round, the steering wheel came away in his hands. He waved desperately to his companion, who had been water skiing for the last fifteen minutes. Both men had hardly had time to realize what was happening when th...

问题 It is time that...与It is time when...的用法疑问

感觉一般是用 It is time that...，但可以用 It is time when...吗？比如：It’s time you _____ threw those shoes in the bin. 你该把缔些鞋子扔进垃圾箱了。不用填空是对，填 that 也是对的，但填 when 对吗？为什么？

话题 如何理解It's been a time 这里用完成时态

问题 why is it that...中it是形式主语吗

Why is it that some people seem to learn several languages without any effort，while for others learning just one foreign language is neither enjoyable nor successful？请...