_____ U2, the Irish rock band from Dublin perform a concert in Beijing, tell me in advance.
| A．If | B．Shall | C．Should | D．Would |
You know that some people say more but do less ________ others do the opposite.
| A．once | B．while | C．when | D．as |
The professor told me to start the research right now, ________ I was sure to fall behind.
| A．or | B．so | C．but | D．and |
________ a man's age, he can reduce it several years by wearing a confident smile.
| A．Whichever | B．Whatever |
| C．Whenever | D．However |
After a year, doctors diagnosed him with a disease so rare ________ it affects just one in 8 million children.
| A．after | B．that | C．as | D．since |
________ you need something, please don't hesitate to let me know.
| A．Even though | B．In case |
| C．As though | D．Even if |