"The plates and the pots are dishes"

Translation: Sahani na sufuria ni vyombo

[AnneLindsa]

why are plates and pots written as singular rather than plural?

[AGreatUserName]

They're both N/N class nouns (class 9/10) so their plural is identical to their singular.

Other words that refer to them may give it away:

sahani yangu = my plate
sahani zangu = my plates

But in this sentence, it's just context. It could also mean "a plate and a pot" or "the..." etc.