落水洞
参考答案:
多分布于较陡的坡地两侧和盆地、洼地底部,也是流水沿裂隙侵蚀的产物。宽度很少超过10米,深可达数十米至数百米。重庆及川南地区称之为“天坑”,一般称竖井。
用括号内所给动词的适当形式填空,必要时可加助动词或情态动词。
Holly is an eighteen-year-old girl. She __1__ (finish) school last year. She __2__ (go) to a bank and
worked as a bank clerk. Now she does well in her work. But she __3__ (want) to be a pianis. She likes
playing the piano and she practices __4__ (play) the piano every day. She says she __5__ (be) a famous
pianist in the future. And her parents agree with her.
油压千斤顶使用时应注意哪些事项?