食管疾病主要症状有_____，_____。
参考答案：咽下困难；胸骨后灼热或疼痛
— Which would you like, a cup of coffee or tea?
— Neither, thanks. I ________ drink a glass of water.
A．prefer
B．like
C．would like
D．would rather
【问题5】 使ADSL的传输速率更高有哪两个主要因素
