Arctan
反正切
🗣️ 情景例句
You go first.
你先来。
My brother's in the army.He was just promoted to the rank of major.
我的兄弟在军队工作.他就被提拔为少校。
They will be able, as it were, to see and hear us in action.
他们能够身临其境般地观看我们做事，倾听我们讲话。