搜题请搜索小程序“爱下问搜题”
问题
单项选择题
乳腺癌发生淋巴结转移最常见的部位是（）
A.颈部
B.锁骨下
C.腋窝
D.胸骨旁
E.锁骨上
答案
参考答案：
C
选择题
— I'm sure Andrew will win the first prize in the final.
— I think so. He ______ for it for months.
A. is preparing
B. was preparing
C. has been preparing
D. had been preparing
查看答案
解答题
计算：
1
a-1
+
1
a+1
-
2a
a
2
-1
查看答案
