人体内产生的二氧化碳、尿素和多余的水分等排出体外的过程叫做( )
A:排废
B:排尿
C:排汗
D:排泄
人工呼吸时最常用的方法是____。抢救时,气体从口中吹入,同时,捏住被抢救者的____。若抢救有效,气体能从被抢救者的____排出。
某同学是学校有名的“小胖墩”,平时一日三餐鸡鱼肉不断,各种巧克力应有尽有.可是该同学却经常感冒,身体素质较差,生物老师对其原因的分析是营养不良.该同学缺乏的营养成分主要是( )
⑴What's your favourite food ?____ A. Ten yuan.
⑵Where do tigers live ?____ B. They live in the forest.
⑶What's for lunch ? ____ C. I like some noodles.
⑷How much is it ?____ D. My favourite food is rice.
⑸Can you swim ?____ E. No, I can't.