写出下列单词的相应形式。
(1)fly(过去式)_________    (2)become(过去式)___________
(3)spend(过去式)_________   (4)our (同音词)_____________
(5)son(同音词)___________   (6)made(原形)_______________
(7)is(过去式)_____________  (8)came(原形)________________
(9)buy(过去式)_____________ (10)went(原形)_______________