Do you remember who gets angry because you forget to tidy up your room before going out? Do you remember who feels 1 with your dress from head to feet? This person is2 your boss nor your friend. It's funny that you have to 3 to her even though you sometimes don't like to hear anything she has said. It’s our mother, a great 4 in the world to us.
I always5 my mother if we have a “long time no see”. But this kind of missing is always quieted down by 6 because I come back home for comfort and 7 but mum always puts more pressure on me. Of course, I know she 8 about me too much and just has a lot of words to tell me. But the 9turns to be pressure. On the other hand, I hurt her and make her feel lonely even though I am 10 her. Then what can we do? This problem is really hard to deal with. I think not 11 I have this problem. Here are my ideas. When we find there are some unhappy things going to12, shall we just stop for 30 13? Give me a chance to rest in your arms and we sing a childish song together just like when I was 14? I need your love indeed but without telling me to do as you wish me to. And then let's go out for a walk hand in hand. Tell me what's in your 15 gently and slowly. I will feel better if you don't just pour them out.
）中的π﹣键不能自由旋转，因此 
和 
是两种不同的化合物，互为顺反异构体．则分子式为C3H4Cl2的化合物的烯烃异构体有（ ）
