影响核酸生物合成的抗恶性肿瘤药物是（）
A.甲氨蝶呤
B.氟脲嘧啶
C.紫杉醇
D.环磷酰胺
E.阿糖胞苷
参考答案：A, B, E
王献之是王羲之的儿子.
Tom and I ________ good friends. He ________ twelve. [ ]
A.are, is
B.am, is
C.is, are
D.are, are
