皮皮学，免费搜题
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【简答题】
What is the purpose of the video library? To help people improve their abilities. 17. What problem may people have when using the library for the first time? They may have difficulties understanding . 18. What are people advised to do when listening to the video? Write down the they hear and understand. 19. What should people do in listening to each conversation? Try to notice the . 20. How can people start watching their first video? All they need to do is to click on the link of .
拍照语音搜题，微信中搜索"皮皮学"使用
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举一反三
【单选题】Father asked her son _______ with his toy plane.
A.
what was the matter
B.
what the matter was
C.
what the matter is
D.
what is the matter
【简答题】在周转转系中,凡具有 几何轴线的齿轮,称中心轮,凡具有 几何轴线的齿轮,称为行星轮,支持行星轮并和它一起绕固定几何轴线旋转的构件,称为 。
【简答题】在周转转系中,凡具有 几何轴线的齿轮,称中心轮,凡具有 几何轴线的齿轮,称为行星轮,支持行星轮并和它一起绕固定几何轴线旋转的构件,称为 。
【简答题】染色体的基本结构单位是 。
【简答题】One d a y.a r ich fa t her took his young son on a tip to the co u n tr yside . He wan t ed to show him how poor the v illager s were and wished him to cherish what he h ad . They spent two days in a ...
【简答题】在周转轮系中,具有固定轴线的齿轮称为 (中心轮/行星轮)。
【判断题】在周转转系中,凡具有固定几何轴线的齿轮,称中心轮,凡不具有固定几何轴线的齿轮,称为行星轮,支持行星轮并和它一起绕固定几何轴线旋转的构件,称为系杆(或行星轮架)。
A.
正确
B.
错误
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