BOB DOUGHTY: Doctors in hospital emergency rooms often see accidental poisonings. A frightened parent arrives with a child who swallowed a cleaning liquid. Or perhaps the harmful substance is a medicine. Or it might be a product meant to kill insec...
⑥最常用的助动词有:be,have,do,shall,will,should,would ⑴ 半助动词 在功能上介乎主动词和助动词之间的一类结构,称为半助动词。常见的半助动词有be about to,be due to,be going to,b...
更多内容请点击：Learning First Aid: What to do until medical help arrives