knotty
Disapproving
例子
The negotiations between the two countries were knotty, with conflicting interests and historical tensions.
两国之间的谈判错综复杂，利益冲突和历史紧张关系并存。
Solving the complex mathematical problem proved to be a knotty challenge for even the most skilled mathematicians.
解决这个复杂的数学问题被证明即使对最有技能的数学家来说也是一个棘手的挑战。
