正确的应该是have the birds fed by anybody
因为该被动句也是疑问语气,还原为陈述句后应该是the birds have been fed by anybody.主语是the birds而不是anybody,所以用have作助动词.
正确的应该是have the birds fed by anybody
因为该被动句也是疑问语气,还原为陈述句后应该是the birds have been fed by anybody.主语是the birds而不是anybody,所以用have作助动词.