Mr. and Mrs. Brown were teachers. They lived in a big 1.Last year they went to the countryside for their summer vacation. They 2 it very much because it was a quite clean place.

    One day they went for a 3 in the morning and saw an old man. He sat in the 4 sun in front of his house. Mr.Brown went to him and asked, “Do you like 5 in this quiet place?”

    The old man answered, “Yes, I 6.”

    Mr. Brown asked, “What are the 7 things about it?”

    The old man answered “Well, 8 here knows each other(互相) well. They often come to see me, and I often go to visit 9, too. Also, there are lots of children here.”

    Mr. Brown said, “That's interesting. Well, 10 are the bad things?”

    The old man thought for a short time and said, “Well, the same things.”

如果集合$M=\left\{y\right|y=\frac{\sin x}{\left|\sin x\right|}+\frac{\left|\cos x\right|}{\cos x},x\ne \frac{k\mathrm{\pi }}{2},k\in Z\}$，则M的真子集个数为（   ）

据统计，目前我国每年吸烟致死人数约有150万。2015年6月1日，被称为史上最严控烟令的《北京市控制吸烟条例》正式实施。条例规定，在禁烟区域吸烟最高可罚200元。对此，欣欣同学发表了评论，下列观点正确的是（   ）

①吸烟体现时尚，偶尔尝试无妨   ②吸烟是成熟的标志

③珍爱生命健康，远离吸烟毒害   ④拒绝不良诱惑，争做文明学生