问题
选择题
They came back to school ______Sunday morning.[ ]
A. in
B. on
C. at
D. for
答案
答案:B
They came back to school ______Sunday morning.[ ]
A. in
B. on
C. at
D. for
答案:B
阅读世界人口变化数据资料表,回答下列问题。
年份 | 1830 | 1930 | 1960 | 1974 | 1987 | 1999 |
人口数(亿) | 10 | 20 | 30 | 40 | 50 | 60 |