头三项链接到目录，而第四项是普通文件。

The first three are links to directories, and the fourth is a plain file.

youdao

在以后的教程，您将了解其他类型的缓冲区，而第四。

In later tutorials you will learn about other types of buffers, and the fourth.

youdao

第一列显示时间，第二列是累计的内存使用量，第三列是增加的内存使用量，而第四列显示函数调用，包括参数。

The first column shows time, the second is accumulated memory use, the third is incremental memory use, and the fourth shows function calls, including the parameters.

youdao

And step four is going to have us figure out how many bonding electrons we have, so we have 16 minus 10, is going to be 6 bonding electrons.

而第四步需要判断,我们有多少个成键电子，那么我们有十六减十，也就是六个成键电子。

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