Iff
[计] 如果仅仅, 当且仅当, \等价\
🗣️ 情景例句
It's not difficult.
这不难。
Heaven helps those who help themselves.
天助自助者。
When the brothers were reunited, Hans explained how it was that he was still alive.
兄弟俩团聚之时，汉斯说明了他活下来的经过，