Armguard
n. 護手
??? 情景例句
That leaves a lot to be desired.
太不讓人滿意了。
Saying is one thing, and doing another.
說是一回事，做是另一回事。
Instruments have been devised and can be so placed that all three elements can be recorded in different graphs.
已經設計出了一些儀器，它按照一定的安放方式就可測繪出這三種運動的曲線圖。