It sounds _______ to use“Could you . . . ”than “Can you. . . ”.
A:polite
B:politely
C:more polite
D:more politely
选项
混合物(括号内为杂质)
除杂试剂或方法
A
Fe 粉(Cu)
CuSO4 溶液
B
CaCl2溶液(HCl)
加过量CaCO3,过滤
C
Na2SO4 溶液( Na2CO3)
过量稀盐酸
D
O2(N2)
通过足量灼热钢网
9216÷72=( )
A:Hello,Tom.
B:Hi,Jenny. How do you feel?
A:I feel happy. Look! This is my sister(妹妹).
B:What's her name?
A:Her name is Kate.
B:What colour is her hair?
A:Her hair is black.
B:What colour are her eyes?
A:They are blue.
B:How nice(漂亮的)!