经过数月的准备，团队开始了穿越喜马拉雅山脉的艰难跋涉。

After months of preparation, the team embarked on the arduous ___trek through the Himalayas.

穿越哥斯达黎加雨林的徒步向导之旅既充满挑战又令人惊叹。

The guided ___trek through the Costa Rican rainforest was both challenging and awe-inspiring.

许多冒险家梦想完成穿越撒哈拉沙漠的多日徒步旅行。

Many adventurers dream of completing the multi-day ___trek across the Sahara Desert.