What should we do to protect the fish in the river？
We_______ throw rubbish into the river．（ ）
| A． |
need |
B． |
needn't |
C． |
must |
D． |
mustn't |
Don't let homework __________ too much time．Children need to play．（ ）
A．give upB．take upC．look upD．put up
I was caught in the rain．Even __________，I was late again!（ ）
A．betterB．worseC．furtherD．worst
Rio 2016Olympics will __________ 16days from August 5th to August 21st．（ ）
A．lastB．continueC．countD．keep
Mum always tells me"A smile costs __________，but gives much．"（ ）
A．anythingB．somethingC．everythingD．nothing
I often feel __________ when speaking in public．
Well，just take it easy．（ ）
A．boredB．greatC．nervousD．serious