---You should have thanked her before you left. ---I meant ____ , but when I was leaving I couldn’t find her anywhere.
28.Which sentence is wrong? 29.
33.I don't think_____________difficult for a Chinese student to master a foreign language within five years 34.
35..It's the second time you_________late this week. 36.
37.It will not be__________we meet again. 38.
39.It's demanded that we____________there on foot. 40.