Los amigos quieren <u>asistir</u> a clases juntos.
Explanation:
English translation: The friends wish to attend the classes together.
The Spanish verb <em>asistir </em>can have multiple meanings, such as to attend - as it is used on the given example -, to help, to assist or even to watch, as in the sentence: "A mi me gusta asistir a los eventos culturales".
