The border guards are on guard.

边防战士在站岗。

I came across this heavily armed Iraqi border guard.

我碰到这个全副武装的伊拉克边防军士兵。

A border guard grumbles that the only tourist in weeks has set off her tripwire.

一个边防人员抱怨说，几个星期只来了这么一位游客，还就触发了她负责的虚拟警戒线。

And during one crossing, a border guard grilled him about what college he attended.

他有一次入境时，一名边防卫兵盘问他在哪儿上的大学。

One border guard, once he got through checking my luggage, said "thank you" in heavily accented English and flashed me a big proud grin.

一个边防士兵在检查完我的行李时，说了句口音很重的“thank you”，并神气的冲我一个咧嘴笑。