Tom
Mary
Jack
Peter
Anna
I have many friends. What are they doing now?
Look!
Look! Tom is watching TV. Mary is reading a book. Jack is drawing a picture. Peter is playing football. Anna is listening to music. They are having fun.
根据以上事实,可得出以下结论:
(i) ____;
(ii) ____;
(iii)若在上述条件下,A、B两种金属与盐酸反应均生成+2价盐,据此还可以得出的结论是____.试对A、B各举一例:A____、B____.
读诗《静夜思》,说说这首诗主要写了:( )