问题
选择题
English is really ________. We must work hard at it. [ ]
A. useful
B. useless
C. easy
D. unimportant
答案
答案：A
搜题请搜索小程序“爱下问搜题”
English is really ________. We must work hard at it. [ ]
A. useful
B. useless
C. easy
D. unimportant
答案：A
下列物质的分类正确的是 （ ）
| 混合物 | 非电解质 | 碱 | 酸式盐 | |
| A | 漂白粉 | Cl2 | 氨水 | NaHCO3 |
| B | 福尔马林 | 苯 | Cu2(OH)2CO3 | 明矾 |
| C | 胆矾 | SO2 | 纯碱 | NH4Cl |
| D | 食醋 | C2H5OH | 苛性钾 | NaHSO4 |