Learn Italian: La cugina è qui e il cugino è lì. - The female cousin is here and the male cousin is there.

Accent marks in Italian often tell apart words that are spelled the same but have different meanings. In this sentence, è (with an accent) means "is", while e (no accent) means "and". Likewise, lì means "there", but li means "them". The word qui (here) doesn't have a twin to confuse it with, so it needs no accent.

How do you show whether a cousin is a girl or a boy in Italian?

By changing the ending of the noun and the word for "the" (the article). La cugina ends in -a and uses the feminine article la, telling us she is a female cousin. Il cugino ends in -o and uses the masculine article il, so he is a male cousin.

What is the difference between qui and lì?

Qui means "here" (close to the person speaking), and lì means "there" (further away). They are great for contrasting where two different people or things are.

We are learning about plural verbs. How would I change this to "The cousins are here"?

You would use the plural form of the verb essere (to be), which is sono (are). For a mixed group of male and female cousins, Italian defaults to the masculine plural, so you would say: I cugini sono qui.