In summer， food will go bad quickly ________ we put it into a fridge．（ ）
| A． |
if |
B． |
unless |
C． |
as soon as |
D． |
while |
My English teacher took a photo of me while I______at the sports meeting． （ ）
A．runB．was running
C．ran
What subject do you like____English， math or physics？
Of course， English（ ）
A．goodB．betterC．best
Who is singing in the next room？
It____be Lisa， but I'm not sure． （ ）
A．mustB．mayC．need
This year is_____70th anniversary（周年）of the founding of the People's Republic of China.（ ）
A．aB．anC．the
Shaoyang has changed a lot in the past few years．
Yes． It is getting_________． （ ）
A．cleanB．cleanerC．cleanest