初中英语
They went to the Great Wall for a picnic yesterday. And they had a long walk_______ the wall. A.along B.on Which one and why?
They went to the Great Wall for a picnic yesterday. And they had a long walk_______ the wall. B.on walk along the wall指的是“沿着墙走”；而walk on the wall指的是“在墙上走”。该句说的是“他们在长城上散步”。
问：已知a,b属于R,求证:a^2+b^2>=a*b+a+b-1
答：答案如下： 由（a-1)^2+(b-1)^2>=0 得到a^2+b^2+2>=2(a+b)--------(1) 又由(a+1)^2+(b+1)^2>=2(a+...详情>>
问：“ prefer to...rather than ”是一个词组吗？
答：prefer to do rather than do sth 与其作后者的事情的不如做前者去事情。 可以等同于= prefer to do instead o...详情>>
