中心型肺癌最常见的早期症状是（）。
A.呼吸困难
B.胸痛
C.声音嘶哑
D.发热
E.刺激性咳嗽、血痰
参考答案：E
—Excuse me, could you tell me____________?
—There is an e–shop on the third floor. You can repair it there.
A．where can I repair my MP4 player
B．where I can repair my MP4 player
C．how can I go to the e–shop
D．how I can go to the e–shop
DN－30浓缩机的直径是（）。
A.25米
B.30米
C.35米
