19．Distinguished guests and friends, welcome to our school! _____the ceremony of the 50th anniversary this morning are our alumni (校友) from home and abroad．

　　　　 A．Attend　　　　 　 B．To attend　　　 　 C．Attending　　 　　 D．Having attended

18．Many people believe we are heading for environmental disaster _____ we basically change the way we live．

　　　　 A．but　 　　　　　　　　　　 B．although　 　　　　　　 C．unless　 　　　　　　　　　 D．once

17．I try to understand __________ that prevents so many Chinese from being as happy as one might expect．

　　　　 A．why is it　　 　　　　　 B．what is it　　 　　　 C．why it is　　 　　　　　 D．what it is

16．---Has Li Lei finished his work today?

--- I have no idea, but he ______ it when I saw him this morning．

　　　　 A．had done　 　　　　　 B．would do　 　　　　　 C．was doing　 　　　　　 D．did

15．Some international organizations _____ the fact that developing and developed countries were in different stages of development and should shoulder different responsibilities ．

　　　　 A．refused　　　 　　 B．denied　　　　 　 C．missed　　　 　　 D．rejected

14．We spent many years studying the formation of rocks, experiencing many sufferings and even death．But our hard work _____in the end, and we made it．

　　　　 A．paid off　　 　　　　 B．made up　　 　　　 C．gave away　　 　　 D．came out

13．---Jenny took the 9:10 bus to Hangzhou this morning．

---Really? He ____ the 9:00 Express．It is much more comfortable and faster to travel by train．

　　　　 A．could have taken　　 　　　　　　　　　　　　　　　　 B．need have taken　

　　　　 C．must have taken　　　 　　　　　　　　　　　　　　　 D．would have taken

12．Some experts think the wolf's team spirit for survival is ____ is needed in today’s competitive culture．

　　　　 A．that　 　　　　　　　　　　 B．what　 　　　　　　　　　 C．which　 　　　　　　　　 D．how

11．--- Can I look at the menu for a few more minutes before I order?

--- Of course．_______, Sir．

　　　　 A．Make yourself at home　　　 　　　　　　　　 B．At your service　　

　　 C．Take your time　　　　　　　 　　　　　　　　 D．It doesn’t matter

10．To prevent cybercrime more efficiently, it is important to make new laws and create international standards for them similar to ______ concerning international airspace．

　　 A．that　 　　　　　　　　　　 B．what　 　　　　　　　　　 C．one　 　　　　　　　　　　 D．those