дарё: river
Дарозтарин дарё дар ҷаҳон дарёи Нил мебошад..
The longest river in the world is the river Nile.
Дарёи Вахш зимистон камоб мешавад.
The Vakhsh river is shallow in the winter.
Bonus:
ча is a suffix that can be used to mean something small. So дарёча is a small river, or a stream.