他们从阿尔巴尼亚穿过边境进入希腊。

They ___crossed from Albania into Greece.

就在我即将穿越美国边境时，我面临了最大的挑战。

It was when I was about to ___cross the U.S. border that I faced my greatest challenge.

火车每天穿越国界。

The train ___crosses the national boundary every day.