Arccos
反余弦
🗣️ 情景例句
Philip, I took Michelle to a school play
Philip,我带Michelle看过学校演出的
Sorrow comes unset for.
悲哀来时不需邀。
I like gardens too, but I do not like hard work.
我也喜欢花园，但我却不愿意辛勤劳动。