get behind
US /ɡet bɪˈhaɪnd/
UK /ɡet bɪˈhaɪnd/

1.
geri kalmak, gecikmek
to fail to make enough progress or to be late with something
:
•
I've got behind with my work.
İşimde geri kaldım.
•
If you miss a few classes, you'll soon get behind.
Birkaç dersi kaçırırsan, kısa sürede geri kalırsın.