下列物质经泌尿、排汗和呼吸三条途径中的两条途径排出体外的是（ ）
①二氧化碳 ②无机盐 ③食物残渣 ④尿素
从方框中选择恰当的句子完成对话。有两项多余。
A. How old are you?
B. May I have your telephone number?
C. I want to join the basketball club.
D. Can you play the violin?
E. W-H-I-T-E ,White.
F. Can you play basketball? G. What club do you want to join?
A: Can I help you?
B: Yes, please. ____
A: OK. What's your name?
B: Sam White.
A: How do you spell your last name?
B: ____
A: Thank you. ____
B: I'm fourteen.
A: ____
B: Yes, but I can't play it well.
A: I see. ____
B: Yes, it's 233-6589.
A: Thank you.
把单位“1“分成3份，其中的2份就是 23 。
