分离下列各组物质一定会用到过滤操作的是（ ）
A．水和汽油
B．蔗糖和水
C．氧气和氮气
D．氯酸钾和二氧化锰
答案：D
春秋晚期杰出军事家_______所著《_______》是世界上最早的兵书。
Directions:
You have trouble with reading and are in need of some advice from Professor Wang.
Write a letter to him to
1) give him your personal information,
2) state your problems, and
3) ask for an interview with him.
You should write about 100 words on ANSWER SHEET 2.
Do not sign your own name at the end of the letter. Use "Li Ming" instead.
Do not write the address.
