下列因素中,与支气管哮喘发作关系最为密切的是()
A.交感神经在支气管中分布少
B.肾上腺素能β受体功能低下
C.三磷酸腺苷增多
D.环磷酸腺苷增多
E.迷走神经兴奋
参考答案:B
I dropped ________ and it wetted the carpet in the sitting room.
A.a coffee cup
B.a coffee’s cup
C.a cup of coffee
D.a cup’s coffee
—Could you please wait for a while? I'll be ready soon.
—Don't worry._________.
A.Take your time
B.It takes time
C.Forget it
D.I don't care