口腔颔面部恶性肿瘤以哪种肿瘤最为常见（）
A.腺源性上皮癌
B.鳞状上皮细胞癌
C.未分化癌
D.各类肉瘤
E.恶性淋巴瘤
参考答案：B
真菌引起的医院感染中，最常见的致病菌是（）。
A.毛霉菌
B.隐球菌
C.光滑念珠菌
D.白色念珠菌
E.李斯特菌
—The Summer Palace is wonderful. Have you ever visited any other interesting places?
—Yes. Also, we _______ to the Great Wall. [ ]
A. have gone
B. have been
C. had gone
D. had been
