Air inside an alveolus gives oxygen to blood and receives carbon dioxide from blood.肺泡里的空气给血液供氧,同时接收血液里的二氧化碳.Through this incision, the abdominal cavity is distended with carbon dioxide gas...二氧化碳气体通过这个切口进入,造成腹腔肿胀。Methan...
I should have simply Xeroxed this sheet for you.我应该把这张纸给你复印一下就对了。We xeroxed thirty sample essays to be graded by all the teachers.我们复印了30份样本短文供所有教师评阅....