Underboarding
垫板, 衬板
🗣️ 情景例句
She was playing with the idea of studying abroad.
她有出国留学的念头，但并非很认真。
Mettle is dangerous in a blind horse.
瞎马鼓勇气，正是危险事。
I seldom have any difficulties.
我很少碰到困难。