Что вставить на месте пропусков? i often the piano.

Ничего не ставим, так как это обычное действие, которое совершается регулярно.
1)I often play the piano. I played the piano yesterday.
2)He cleans his room every Saturday. He cleaned his room last Saturday. 3)She always asks a lot of questions. She asked five questions yesterday. 4)Little Tom likes to collect things. Last year he collected little cars, now he collectes postcards.
5)Granny always answers letters. Yesterday she answered two letters.