I like hiking in the forest because the air is pretty ______．（ ）
A．freeB．dirtyC．pollutedD．fresh
I don't know how to use the App Fun Dubbing．
Ask Kitty for help． She has lots of in doing it．（ ）
A．expressionB．experiment
C．examinationD．experience
John _______ so hard on his project that he didn't notice his mom enter the room．（ ）
A．worksB．has worked
C．was workingD．will work
Alice's room is tidy， isn't it？
Yes． She always _____ her toys after playing with them．（ ）
A．looks forB．puts away
C．sweeps awayD．pays for
Do you like rock music or light music？
_______． I like Beijing Opera．（ ）
A．EitherB．NoneC．BothD．Neither
I've ordered some flowers for grandma and they will arrive _____ two hours．（ ）
A．inB．afterC．overD．for