输尿管肿瘤的特点（）
A.多发或孤立存在
B.输尿管下段常为好发部位
C.由肾盂肿瘤蔓延、种植形成
D.由膀胱肿瘤向上蔓延而来
E.以上都对
参考答案：E
给4：7的前项加上8．要使比值不变，后项应该加上14．______．
______ we talk to each other, I feel happy.
A．Every time when
B．Every time that
C．Every time
D．Every time which
