external接口指的是外部接口，用来从外部传输文件的接口

例句

1、

Many external influences can affect your state of mind.

许多外在因素都可能影响人的心情。

2、

A combination of internal and external factors caused the company to close down.

内外因结合导致了公司的倒闭。

3、

The state has a duty to protect its citizens against external enemies.

国家有义务保护本国公民不受外敌侵犯。