环磷酰胺对下列哪种肿瘤疗效最好( )
A．多发性骨髓瘤
B．恶性淋巴瘤
C．急性淋巴细胞性白血病
D．乳腺癌
E．卵巢癌
参考答案：B
All the students injured in that accident are still in hospital, ________for further observation. [ ]
A. kept
B. keeping
C. having kept
D. to be kept
-Could you come back home 9:30?
-I'm afraid not. I'll have a meeting at 9:00. [ ]
A. by
B. until
C. with
D. after
