Ethynylation
炔化, 乙炔化作用
??? 情景例句
Yes, I went to the aerobics class today.
去了啦， 我上了有氧運(yùn)動課了。
A wise man needs not blush for changing his purpose.
智者不恥于改變初衷。
Which man?
哪個(gè)人？