白果在定喘汤中的作用是
A．散寒平喘B．敛肺定喘C．清泻肺热D．止咳化痰E．降气平喘
参考答案：B
Tom's mother demanded that she ________ everything on time. [ ]
A. would tell
B. tell
C. have told
D. be told
李师傅锯一段长20米的木材，锯4段用了6分钟，每段长______米，如果锯成12段要用______分钟．
