问题
单项选择题
Radio beacon service of John Light（）discontinued.
A.has been
B.have been
C.have
D.has
答案
参考答案：A
搜题请搜索小程序“爱下问搜题”
Radio beacon service of John Light（）discontinued.
A.has been
B.have been
C.have
D.has
参考答案：A