要使用不同的登录名称，请在主机名前加上该登录名称，并使用 @ 符号分开。

To use a different login, prefix the hostname and separate the two with the @ sign. For example

youdao

您可能已经看到，XQuery 中通过在标识符前加上美元符号（$）来定义变量。

You've already seen in XQuery that a variable is defined by putting a dollar sign ($) in front of an identifier name.

youdao

到公元前2300年，所需的符号数量已减少到600个，词汇可表达的范围也扩大了。

By 2300 B.C.E. the number of signs required had been reduced to 600, and the range of words that could be expressed had widened.

youdao

If you give a sign, on top of the number, that takes care of all ambiguity in one dimension.

如果你在数字前加一个符号,就把一维运动的所有的歧义解决了

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