发布于：2025-07-06 05:56浏览量：185文/优校网
1.要点;症结;难题,难点;难解的谜
2.【纹章】十字(架)形
3.【天】南十字座
1.an essential or deciding point or element in something, e.g. in an argument
2.an extremely difficult or puzzling problem
3.the most demanding part of a climb up a mountain or rocks