题目

—Mr. Lee's history class is interesting. —_______. We all like him. A . I don't know B . That's for sure C . That's OK D . Thank you 答案：B（2009?贵州）下列粒子都能直接构成物质的是（　　）A．分子、中子B．原子、电子C．原子、离子D．离子、中子