我国处理民族关系的原则是 [ ]
A.平等团结互助和谐
B.“三个尊重”
C.民族区域自治制度
D.民族平等、团结和共同繁荣
答案:D
Mr Lin, a famous writer, _______ our school last week.
A.visits
B.will visit
C.is visiting
D.visited
在任何情况下,只要沉降器、汽提段内有催化剂,就必须保持分馏塔底油浆循环从上进口返塔。