"play piano" vs "play the piano"

Can anyone tell me the differences between “play piano” and “play the piano” ?
=> When we say “I used to … when I was three; I don’t now” , we use “play piano” or “play the piano” to fill in the blank ? :roll:
== One more thing : which one do you use to complete this sentence :
=> Last week, the bank told me my bank account didn’t have money left. I … it all
a. had spent
or
b. spent
Thank you!

pm: pirates_of_caribbean93@yahoo.com.vn

Jack, either of your sentences are both correct, regarding the piano. Both are freely used.

I had spent it all, is the sentence to use.

But Kitosdad, some time we stuck whether we should use THE or not ? How to clear this hurdles ?

Thanks
Kirti