This is the 1st most frequent Vietnamese word.
và
"Và" means "and" in English.
Here, 'và' serves as a coordinator to connect two subjects ('the cat' and 'the dog') in the sentence.
Con mèo và con chó này rất thân thiện.
The cat and the dog are very friendly.
In this sentence, 'và' is used as an enumerative conjunction to combine two nouns ('apples' and 'oranges') in a list.
Tôi mua táo và cam ở siêu thị.
I bought apples and oranges at the supermarket.
In this case, 'và' connects two clauses with related ideas, acting as a transitional conjunction.