He finished _____ the composition just now. [ ]
A. write
B. writes
C. to write
D. writing
D
喉咽部恶性肿瘤根据发生部位可位于()
A.梨状窝癌
B.会厌癌
C.环后癌
D.喉咽侧壁癌
E.喉咽后壁癌
皮带输送机的皮带连接一般采用粘接,请回答什么叫粘接?