透镜有两类:中间厚边缘薄的透镜叫______,它对光有______作用,中间薄边 发布时间:2017-05-26 15:23 │ 来源:www.tikuol.com 题型:填空题 问题: 透镜有两类:中间厚边缘薄的透镜叫______,它对光有______作用,中间薄边缘厚的透镜叫______,它对光有______作用.
题型:填空题 —What do you use computers to do? —They are useful. For example, they can _ sending e-mail. [ ]A. use to B. be used of C. be used for 查看答案
题型:填空题 Compared with this year, the estimated world oil growth for 2005 will ______. a. be 84 million more barrels per day b. increase by 2.5% c. be up 2.53 million barrels per day d. be up 1.8 million barrels per day 查看答案