问题
选择题
Are the two glasses believed________by Tom?
A.broken
B.to be broken
C.to break
D.to have been broken
答案
答案:D
Are the two glasses believed________by Tom?
A.broken
B.to be broken
C.to break
D.to have been broken
答案:D
下列各组物质能按照关系图(“→”表示反应一步完成相互转化的是)[ ]
X | Y | Z | |
A. | C | CO | CO2 |
B. | CaCO3 | Ca(OH)2 | CaO |
C. | Na2CO3 | NaOH | Na2SO4 |
D. | Fe2O3 | Fe | FeCl2 |