阅读理解

    It is Sunday today. It is my grandma's birthday. Father, mother and I go to visit her.

    She lives with my uncle. In the morning we buy a birthday cake and some fruits and go to her house at ten o'clock.

    We spend about half an hour getting there. My grandma and uncle are very glad to see us. We give the presents to grandma and say“Happ y birthday to you! ”She is very happy. Then we sit down to talk. My uncle can cook.

    The meal is very nice. We all like it very much. After lunch, I play with my uncle. At four o'clock, we say goodbye and go home.

阅读《春》选段，完成下面题目。                    
         ①“吹面不寒杨柳风”，不错的，像母亲的手抚摸着你。风里带来些新翻的泥土的气息，混着青草味儿，还有各种花的香，都在微微润湿的空气里酝酿。鸟儿将巢安在繁花嫩叶当中，高兴起来了，呼朋引伴地卖弄清脆的喉咙，唱出宛转的曲子，跟清风流水应和着。牛背上牧童的短笛，这时候也成天嘹亮的响着。
        ②雨是最寻常的，一下就是三两天。可别恼。看，像牛毛，像花针，像细丝，密密地斜织着，人家屋顶上全笼着一层薄烟。树叶却绿得发亮，小草也青得逼你的眼。傍晚时候，上灯了，一点点黄晕的光，烘托出一片安静而和平的夜。在乡下，小路上，石桥边，有撑起伞慢慢走着的人，地里还有工作的农民，披着蓑戴着笠。他们的房屋稀稀疏疏的，在雨里静默着。

—Of course, it's built over a         canyon in the Zhangjiajie National Forest Park.

一列数a₁，a₂，a₃，…，其中a₁=$\frac{1}{2}$，$a_n=\frac{1}{1-a_{n-1}}$（n为不小于2的整数），则a₁₀₀=（   ）