通读下面短文，掌握其大意，然后在每小题所给的四个选项中，选出一个最佳答案。

    It's a fine Saturday morning. There are many people in the park. Many of 1  are young and some are old.

    Some children are 2  games over there. Two boys are playing  3 their toy bats. There is a lake in the park. The water is 4  .  There are some 5  on the lake.  6  the lake a young man is reading. There is a house near the lake. Beside 7 house two men are working. Look at that big tree! There are some birds 8  it. Under it are some men. Four of them are playing cards. One of them is looking at two cats. The cats are 9 up the tree. What do they 10  to do? They want to catch the birds.

为下列加线字注音：

骸骨____  鲦鱼____ 窒息____  巉岩____  踉跄____  辗转____  吹毛求疵____

在匀强磁场中，一矩形金属线框绕与磁感线垂直的转轴匀速转动，如图1所示，产生的交变电动势的图象如图2所示，则（   ）

假如地震发生时，我们正在家里，正确的方法是（    ）