W hen we got to the cinema the tickets have been _____(卖完).

问题描述:

W hen we got to the cinema the tickets have been _____(卖完).
have been 不是加doing吗?为什么可以加sold

sold  out
问题补充:
have been 不是加doing吗?为什么可以加sold
---have been doing 是“现在完成进行时”
而 这里是现在完成时的被动语态