题干
- When is Lang Lang's concert?
- It's three o'clock the afternoon of December 18th.
A：at; in
B：at; on
C：on; in
D：in; on
答案(点此获取答案解析）
B
- When is Lang Lang's concert?
- It's three o'clock the afternoon of December 18th.
A：at; in
B：at; on
C：on; in
D：in; on
3H2O+2CO2的认识，错误的是（ ）