is this problem ( ) the teacher explained last week A.which B.that C.the one D.one为什么不选ABD,而选C. 尤其是D.请解释的简单明白一些,谢谢.可以的话请区别一下one和the one,谢谢啦~

this is a （ ) problem This problem is very___for her. __ __ THIS MATHS PROBLEM IS ! It is difficult () out this maths problem This problem is not above us . this problem is difficult and ---------- (bore). This problem is more difficult than that one.This problem( ) ( ) ( ) ( )that one. This problem is easier than any other one in this exam.(同义句转换) This problem is ( ) ( ) ( ) inThis problem is easier than any other one in this exam.(同义句转换)This problem is ( ) ( ) ( ) in this exam. 这个句子this problem is hard to be solved.this problem is hard to be solved.this problem is hard to solve.是不是两个都是正确的呢? This problem is far from 接being settled 还是settled This is not a problem since during the inspection是什么意思, l think this problem is e_______ of the three. this problem is very easy A----- can do it is this maths problem 要用easy还是easily This problem is ( ) difficult ( ).第一空为什么不能用very There is no simple -----(solve)to this problem. so this is not where the problem lies. this problem is not difficult.you can do it ( ).