Unit 4 HomeworkUnderline the topic sentence in the following paragraphs.Paragraph oneThe high school students often have to study deep into the night, and their parents become worried. The parents think that they might get ill if they continue like that, so some of them try to persuade their children to work less and rest more. But most of the boys and the girls do not dare to relax even a little. As a result, the parents have to turn to the teachers for help and ask them to assign less homework.Paragraph twoIn some places of Peru and Bolivia, one speaks of the future as behind oneself and the past as "ahead". It makes foreigners puzzled. But the people in those places will explain it by saying: "If you try to see the past and future with your mind’s eye, which can you see? Obviously, it is the past that we can see and so it must be ahead of us: and the future which you cannot see, is of course behind you. Such an explanation suggests that there may be opposite ways of describing the same thing, yet they are both reasonable.Young people move out and mind their own business every day. On usual days, they would not like to take their time to visit their parents with the excuses of business. On some festival days, they probably share a little time to drop in their parents or even just send some presents but don’t show up personally. They think that presents can represent their love, however, to the parents, who overcame a lot of difficulties to bring them up, those stuff are far away from what they really hope for.