So if I want to use a string as we'll call it which is a word or phrase generally, they always go between double quotes, David hence the quotes around David, and they are double quotes not single quotes intentionally.

当我们要表示单词啊，词组啊，句子啊等等这样的东西时,就会用到字符串，它们位于双引号之间，也就是这里双引号之间的，是双引号，不是单引号哦。

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