1.He______to play______before he was 11 years old.

1.He______to play______before he was 11 years old.
A.had learned,piano B.had learned,the piano
C.has learned,the piano D.learned,piano.
2.What______Annie______by the time he ten?
A.did,do B.did,did C.has,done D.had done
3.By the time he was 4,he______a lot of German words
A.has completed B.completed C.will completed D.had completed
4.The train from Beijing_______ten minutes ago.
A.has arrived B.was arrinving C.arrived D.had arrived
5.The man______his coat and went out.
A.put on B.had put on C.will put on D.was putting on
6.He______in the factory for three years before joined the Army
A.has worked B.works C.had worked D.will work
7.Tom _______the project in one hour.
A.have finished B.will finish C.finishes D.has finished
过去完成时和过去过去进行时的结构是什么?