乙酸和乙醇是生活中两种常见的有机物，可反应生成有香味的化学物质A．
下列生物中属于单细胞生物的是（ ）
补全对话，每空一词。
A: ____ time do you usually get up, Bob?
B. I usually get up ____ 6 o'clock.
A. So early? What do you do then?
B: I ____ my teeth and ____ a shower. Then I eat my breakfast.
A: ____ do you go to school?
B: At 8 o'clock.
