从一个细胞到“小帅哥”，让我们看到了生命发生的奇妙变化。

（1）我的生命开始于一个被称为____ 的细胞，出生前的我舒适地生活在妈妈的____ 里，每时每刻，都能通过____ 和____ 从妈妈那获得营养。
（2）大家说我长得像妈妈，这是一种____ 现象。不过，作为男孩子，我体细胞中的性染色体组成是____ 。
（3）青春期的我开始长胡子了，这和性器官中的____ 分泌的雄性激素有密切的关系。我要积极锻炼，努力学习，不虚度青春好时光。

    I will have a holiday next week and I can't decide what to do. I have a lot of work to do 1 and this would be a good chance 2. But I don't like 3 the holiday in such a way.I can work at home all the rest of the year.

    Last year I went 4 to the mountains. 5 there was beautiful， but it is too cold this time of a year. And it's really6 far to go for a short holiday. I decide 7 this isn't a good time to8the mountains.But I9to go somewhere else.Perhaps this would be a good chance to go to the beach（海滨）.I like to go for walks10the seashore 11the warm sunshine and watch the water. It's only eight miles away and I could get there 12about two hours. After thinking it13，I am sure that this is a 14time for the seashore than15.

    Oh， here is a 16from Jim. He 17 he is going to his house in the mountains for the18，and he19me to go with him.20 giving it some more thought， I wrote back to Jim and thanked him for that.

要测量小敏同学上楼梯时的功率，不需要测量他的（　　）