The linked composite sentence. Copulative conjunctions

The copulative conjunctions va and hamda join parts of a composite sentence that stand in a relation of time or reason-result. Events may happen in sequence or at the same time: “Eshik ochildi va xona yorishdi”. If there is a reason-result relation, the word “natijada” can be put before the second part: “Shamol kuchaydi va (natijada) derazalar taqilladi”. Sometimes the particles -u (-yu) and -da also work as copulative conjunctions: “Yomg‘ir tindi-yu, quyosh yana charaqladi”. Remember: “va” also joins homogeneous parts, so to tell it from a composite sentence we must count the predicates. Between parts joined by a copulative conjunction a comma is usually not put, but after -u (-yu), -da a comma is put.