如图，有一圆柱体，它的高为8cm，底面周长为12cm．在圆柱的下底面A点处有一个蜘蛛，它想吃到上底面上与A点相对的B点处的苍蝇，需要爬行的最短路径是____ cm．

根据括号里所给的汉语写出英语单词。

1.Try to____ （步行)or ride a bike when you travel a short distance.

2.Chinese people usually eat ____  (月饼) on Mid-autumn Day.

3.It isn't ____  (容易的) to learn English well.

4.Do you want to____ (制作) cards by hand for your teachers on Teachers' Day?

5.Cars pollute the ____ (空气)，so remember: Use your legs