two of strings和two strings的区别?

two of strings和two strings的区别? Two of the strings为什么不能Two strings two of the strings 和a relative of the patient 为什么都不加’s?不都是a friend of my farther‘s 为什么这两个最后都不加一撇s呢? two of strings 可不可以改成 two stringstwo of strings were broken.可不可以改成two strings were broken.在语法上有没有问题啊? she struck the keys too hard and two of the strings were broken.直接永two the strings可不可以? She struck the keys too hard and two of the strings were broken.two 后 为什么有 of the .为什么不能直接是two strings She struck the keys too hard and two of the strings were broken.这句话里面two 后面为什么要加of呢? two different kinds of book 和 two kinds of different books 有什么区别?是不是两者都可以.two different kinds of books，忘了加s了 two glass of waters和two glasses of waters He has two pairs of s( )shoes there ( is)two slice s of bread? two pairs of shoe加不加s, in two shakes of a lamb's What's the meaning of Two to two to tow two in two minute s和after two minutes的意思? two score of 和two score 的 区别 It`s Two Two Too two thousand of 和thousands of 区别