There are some words_______can cross countries and cultures，such as“OK”．“Huh’’and“mama”．
A．what B．which C．／
I don’t know ______ with this problem. It’s too hard.
| A．which to do | B．when to do |
| C．what to do | D．how to do |
The notebook ___________ be John's ．There is his name on it．
| A．must | B．might |
| C．could | D．can't |
_____you go, ____you do in your school, You must obey the rules．
| A．Wherever; whatever | B．Where; what |
| C．Whatever; wherever | D．What; where |
Tony didn't run ________．He was behind all the other runners．
| A．slowly enough | B．fast enough |
| C．enough slowly | D．enough fast |
He used to like playing________ piano，but now he likes playing _________ basketball．
| A．／：the | B．the；the |
| C．a：／ | D．the；／ |