翻译句子The most common machine element is the gear, which combines the feature of the wheel and the lever to form a toothed wheel.
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翻译句子The hardness of a gear determines its ability to resist wear.
翻译句子Manufacturing engineers have centered their efforts on the development of standardized elements.
Powerpoint中,执行了插入新幻灯片的操作,被插入的幻灯片将出现在( )
A. 当前幻灯片之前
B. 当前幻灯片之后
C. 最前
D. 最后
在一页Powerpoint中，图片1把图片2覆盖住了，若要设置为图片2覆盖图片1,应使用( )
A. 选中图片2→置于顶层
B. 选中图片2→置于底层
C. 选中图片2→旋转
D. 选中图片2→组合
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