采用供液过冷后,使节流过程中产生闪发气体量()。
参考答案:减少
I thought _____ no use talking with him. _____ was a waste of time.
A.there…There
B.it…It
C.there…It
D.it…There
视图不能单独存在,它必须依赖于( )。
A.视图
B.数据库
C.数据表
D.查询