they are singsing a beautiful song for the old man改成被动语态
问题描述:
they are singsing a beautiful song for the old man改成被动语态
答
中间空格应为 is being sung 因为原句是进行时
they are singsing a beautiful song for the old man改成被动语态
中间空格应为 is being sung 因为原句是进行时