-I haven't seen your English teacher for a week. Where is he?
-Sorry, I don't know _______.
A:where has he been
B:where he has been
C:where has he gone
D:where he has gone
为____(结果用根号表示).
①坚持国有经济在国民经济中的主体地位,增强控制力 ②各种所有制资本取长补短,共同发展
③国有资本放大功能与保值增值,提高竞争力 ④取消不同所有制企业的市场准入门槛,实现公平竞争