问题
选择题
They ______ English lessons on Friday. [ ]
A. doesn't has
B. doesn't have
C. don't have
D. aren't have
答案
答案:C
They ______ English lessons on Friday. [ ]
A. doesn't has
B. doesn't have
C. don't have
D. aren't have
答案:C
下列各组物质,不能按照关系X—Y—Z—X(“—”表示反应一步完成)相互转化的是
物质 | A | B | C | D |
X | CaO | BaCl2 | Cu(NO3)2 | K2SO4 |
Y | CaCl2 | Ba(NO3)2 | Cu(OH)2 | KCl |
Z | CaCO3 | BaCO3 | CuSO4 | KNO3 |