一般检查片的取出应每隔()年进行一次,从中获得管道保护经验。
A.一
B.二
C.三
D.五
参考答案:A
Mr. Ford saw a nice sweater in the shop window. It was very c_______. So he bought one. When he went back home he put the sweater o________, It was all right and he felt very h_______. In the afternoon he went out to work in his garden. It suddenly began to r_______, and Mr. Ford had to run into his house. He ran q_______, but he still got w_______. Then his sweater s________ to shrink(缩水). It got smaller and smaller. Mr. Ford t_________ to take it off, but he couldn’t. In the end, with the h_________ of his wife, he got out of the sweater. Mrs. Ford l________ and said, “ You see, you bought a cheap thing, but…”
谷坊的类型,如何计算谷坊水平间距?