由锅炉、汽轮机、凝汽器和给水泵等组成的系统叫做（）系统。
A.蒸汽
B.给水
C.汽水
D.发电
参考答案：C
— Has Tom finished writing his essay today?
— I have no idea. He ______ it this morning.
A．wrote
B．has written
C．was writing
D．had written
会计、财务、税务、金融都会产生与专利有关的职业岗位，例如（）
A.专利律师
B.发明人技术顾问
C.上市公司无形资产会计
D.专利质押顾问
