将线段AB延长至C,再将线段AB反向延长至D,则图中共有线段( )条.
A.8
B.7
C.6
D.5
线段上有4个点时,线段总条数是3+2+1条,即6条.
故选C.
—You went to the US last month , didn’t you?
—Yes. That was the first time that I________ there.
A.went
B.had gone
C.had been
D.have been
缺铁性贫血周围血象主要特征是
A.以血小板数降低为主
B.以自细胞数减低为主
C.以网织细胞数增加为主
D.以血红蛋白量减低为主
E.以红细胞数减低为主