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

trek 是名词，指"长途徒步旅行"，通常指在崎岖地形或野外环境中进行的徒步活动。这个词源自南非荷兰语，原指"牛车旅行"，后来演变为指艰苦的长途跋涉。