To some people,traffic problems were everyday occurrences.Nevertheless,an accident between a car and a horse-drawn carriage____1____ a green light in the mind of one witness to it.__2___,thought Garrett A Morgan,design a signal that would __3__ the movement of road traffic?______,in February 1927 Morgan and produced the world's first automatic electric traffic signals.
The word "stop"and "go"were on different sides of the arms,which automatically turned and faced the__6__line of traffic when necessary.
He went on to start a company selling hair treatments and later he invented the "safety hood",which__9__firemen from gas and smoke and won a prize at a 1914 exhibition.
1.A.turned on B.hit C.knocked D.shut
2.A.Isn't it necessary B.How about
C.What if D.Why not
3.A.direct B.master C.rule
4.A.In other words B.Above all
C.For example D.As a rule
6.A.long B.right C.straight
9.A.prevented B.protected

这篇问题比较多，所以我基本上把关键段落都打下来了，选项删减过，剩余的都是我不能排除的，所以尽可能请解释下每个选项（另外翻译一下含题目1，4的句子，4主要是选哪个短语放到句子里我都觉得不通顺）工作量比较大，先谢谢了！！！

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