形容詞 perilous:

1. fraught with danger
   同義詞：parlous, precarious, touch-and-go

1. It is true during their explorations they often faced difficulties and dangers of the most perilous nature.
   確實(shí)在探險中，他們經(jīng)常面臨著各種最有危險性的艱難和險阻。
2. Their perilous journey across the ocean has attracted public attention.
   他們的越洋冒險旅行引起了公眾的注意。

per.il.ous

adj.（形容詞）
Full of or involving peril; dangerous.
充滿或包含危險的；危險的

【引伸】
per.ilously
adv.（副詞）
per.ilousness
n.（名詞）