酒钢选矿厂采用的抑制剂是()。
参考答案:淀粉
Lynn's mother is a nurse. She works in a .[ ]
A. shop
B. school
C. hospital
--- Has your brother returned from America yet?
--- Yes, but he ______ here for only three days before his company sent him to Africa.
A.has been
B.was
C.will be
D.would be