This model of typewriter is ________ and ________ , ________ and ________ for middle school students. 这个型号的打字机对中学生来说高效、耐用、经济和实用 2. The computer we produced is characterized by its________ , ________, ________and it’ also ________. 我们生产的电脑以高品质 , 结构紧凑、节能、操作简易而著称 3. They are not only as________ as other makers, but they are distinctly ________ in the following respects . 他们不仅与同等产品一样价位低廉 , 在以下一些方面更具有过人之处 4. You will get a 30% ________ upon using this machine and also it allows one people to perform the task of three people. 使用这台机器你能提高 30% 的产量 , 它可以让一个人执行三个人的任务 5. This product will ________ in a year. 这个产品在一年内能够 6. This machine will pay back your________in 6 month. 这种机器 6 个月内就将让您收回投资 7. The new type of suitcase card designed by our engineers is very ________and ________. 由我们的工程师设计的这种密码箱非常的精巧实用 8. This kind of bicycle can ________in half and handy to carry around ,especially useful during traveling and traffic jams. 这种自行车可以对折 , 能够手提携带 , 在旅游和交通堵塞时特别有用 9. The ________of this kind of variable speed bicycle is 30 K/H . 这种变速自行车的最大速度为 30 K / H 10. These machines have few________ and easy to ________ because of their simple mechanical structure. 由于机械结构简单,这些机器故障少 , 易于维护 ,