5.Thesweetestintheworldisbirds'singing,Ithink.(C)A.noiseB.soundC.voice6.It'snothingserious.You'vejustcaughtcold.(B)A.alittleB.abitof7.Hecasthisnetthirdtime,anddrewinalotofstones.(A)A.aB.the希望能够

Question

5.The sweetest _____ in the world is birds' singing,I think.(C)
A.noise B.sound C.voice
6.It's nothing serious.You've just caught ______ cold.(B)
A.a little B.a bit of
7.He cast his net ____ third time,and drew in a lot of stones.(A)
A.a B.the
希望能够多答案进行分析,最好把别的选项不正确的理由写一下.

Answer 1

5.noise 多指噪音,sound指一切声音,面太广,而voice 多指动物发出的鸣叫声；
6.cold 在此为可数名词.我们可以说 a cold,而 a little 用于不可数名词.
7.如果用“the”,须在前面加 "for".