What chores do you _______do?
A:have to
B:have
C: /
D:having
CH3CH2C(CH3)2C(CH2CH3)2CH3.
皂甙具有抗菌、防癌作用,皂甙的化学式为C27H42O3.下列关于皂甙的说法不正确的是( )