was playing the piano
Tom cantó mientras Mary tocaba el piano.
Tom sang while Mary played the piano.
Ella tocaba el piano con entusiasmo.
She played the piano with enthusiasm.
Él tocaba la guitarra y ella tocaba el piano.
He played the guitar and she played the piano.
Él tocaba el piano y ella cantaba.
He played the piano and she sang.
Ella tocaba el piano en ese momento.
She was playing the piano at that moment.
He played the piano.