问题
单项选择题
When catching an airplane, you'd better be earlier, and therefore you can avoid the frustration of arriving at the very moment when the plane is taking off and______unable to get on it.
A．be
B．are
C．being
D．were
答案
参考答案：C
解析：being unable to get on in 与arriving at the very moment…并列，作介词of的宾语。
