Combinatorics
n. 组合学,组合数学
🗣️ 情景例句
To help scrub the building interior clean.
帮忙把建筑的内部擦洗干 。
If it were not for hope, the heart would break.
人是靠希望活著的。
How do you want your steak?
你的牛排要几分熟？