This is Mary. She is a good friend of ______.[ ]
A. me
B. mine
C. my
D. I
答案:B
下列算式中,正确的是( )
A.7xy-7yx=0
B.-5x3+2x3=-3
C.3x+4y=7xy
D.4x2y-4xy2=0
接触性皮炎常见的皮损形态为()
A.丘疹、脓疱
B.红斑、水疱
C.抓痕、结痂
D.风团、糜烂
E.苔藓样变或色素沉着