Write questions.Use present perfect progressive.
1) How long you (do) these exercises?
2) Since when you (paint) this picture?
3)How long she (wait) for her lunch
4)Since when they (grow) these plants?
5)How long she (stay) at this hotel?

1.How long have you been doing these exercises?2. Since when have you been painting this picture?3.How long has she been waiting for her lunch?4.Since when have they been growing these plants?5.How long has she been staying at this hotel?