I had been looking for it for days before I found it.
They had only been waiting for the bus a few moments when it came.
He had been mentioning your name to me.
You had been giving me everything.
The doctor asked what he had been eating.
I asked where they had been staying all those days.
I had only been reading a few minutes when he came in.
She'd only been reviewing her lessons for a short while when her little sister interrupted her.
I had been sleeping when my friend telephone me.