A:书到用时方恨少,是非经过不知难
B:纸上得来终觉浅,绝知此事要躬行
C:自古学问无遗力,少壮功夫老始成
D:书山有路勤为径,学海无涯苦作舟
American women usually identify their best friends as someone _______ they can talk frequently.
电解质
非电解质
强电解质
弱电解质
A
Cu
NH3
H2SO4
CH3COOH
B
SO3
蔗糖
NaOH
H2CO3
C
酒精
KCl
BaSO4
D
BaCl2
SO2
NaCl
at for in with to