俄罗斯煤的蕴藏了居世界第()
A. 一
B. 二
C. 三
D. 四
Johnson said that the evening party would cost him 200 dollars. But the expense ________ was 300 dollars.
A. really
B. true
C. actual
D. certain
When the holiday starts, I will try ________ my research ideas.
A. out
B. in
C. with
D. up
利用膜将水中的物质( )出去的方法称为水的膜析处理法
A. 渗析
B. 纳滤
C. 超滤
D. 分离