Here's a breakdown of the phrase:
* Me gusta: This is the present tense of "gustar" which means "to like". The "me" at the beginning indicates that the speaker is the one who likes something.
* pasar tiempo: This means "to spend time".
* con ellos: This means "with them". "Ellos" is the masculine plural pronoun for "they".
Therefore, the entire phrase expresses the enjoyment of spending time with a group of people.