Nine thousand guests took part in the outdoor ceremony, ______ that impressed so many people at the White House．
| A．that | B．this | C．it | D．one |
___ we know some basic knowledge concerning AIDS, we can protect ourselves from being infected.
| A．If only | B．Even if | C．So long as | D．Unless |
--- How did you like Nick’s performance last night?
--- To be honest, his singing didn’t ___to me much
| A．accustom | B．appeal | C．occur | D．refer |
I don’t think Jack is a man to be ______ when we are in trouble. He only cares for himself.
| A．relied on | B．familiar with | C．turned to | D．based on |
____ is mentioned above, the number of students in senior high schools is increasing.
| A．What | B．That | C．Which | D．As |
According to a UN report, some 844 animals and plants ______ in the last 500 years.
| A．disappeared | B．were disappeared |
| C．have disappeared | D．had been disappeared |