室温下呈液态的油脂称为 ,例如 ;室温下呈固态的油脂称为 ,例如 。
油 ;豆油 ; 脂 ; 猪油
函数y=tanωx(ω>0)的最小正周期T=π,则ω=______.
—What do you want to do with the pollution?
—It makes me _____ a clean-up campaign. [ ]
A. to join
B. to join in
C. join
D. join in