双子叶植物的根的性状特征为
A.一般为直根系
B.表面常为栓皮,较粗糙
C.形成层环大多明显
D.中心常无髓
E.自中心向外的放射状结构,木部尤为明显
参考答案:A,B,C,D,E
-May I come in? I'm sorry I am late.
-Come in, please. But could you please tell me ?[ ]
A. what were you doing then
B. why are you late again
C. who you talked with
D. how did you come to school
常用的软膏剂基质分为
A.油质性基质和水溶性基质B.油质性基质、水溶性基质和乳剂型基质C.油质性基质和乳剂型基质D.水溶性基质和乳剂型基质E.凝胶性基质和乳剂型基质