不溶于水的物质是()。
A.食盐
B.丙酮
C.乙醇
D.煤油
参考答案:D
While you were in London that year,the London Bridge______.
A.was being repaired
B.had been repaired
C.would be repaired
D.was repaired
中国公关实务的专业化程度日渐提高的主要表现是什么?