You need to do that to be able to control the shield that's as big as that and as heavy as that, because it is made fundamentally of a heavy wood, typically covered by leather, sometimes with some bronze, a bronze sheet across the front of it as well.

如果你想自如操控这块盾牌就必须得这样,这种盾牌很大并且很笨重,因为它主要是由沉重的木材制成,表面一般覆有皮革,或包上铜皮,就是表面上有一层铜皮

耶鲁公开课 - 古希腊历史简介课程节选

And most of these commands you don't actually need but this little caret symbol means control, so every keyboard these days has a control key so you hold that and hit X for instance to exit the program.

这里大多数命令你们都用不着,这个小插入符意味着控制，每个键盘都有一个控制键,譬如，当你敲入X时，就退出这个程序。

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