If You Did Previous Graduate Work Elsewhere
The university allows up to 2 courses taken elsewhere, with a grade of B or better and not used for any previous degree, to count towards the M.A. In our program that means an equivalent of psycho-/computatational linguistics, or an elective course. To transfer the course credit from the original institution to UCLA, you must file a petition (see the Graduate Student Affairs Officer).
If you were at another UC campus, then things work a bit differently: up to half your graduate courses can be transferred; that would mean up to 4 courses, though not the required syntax, phonology, or semantics courses (200A, 201A, 200B, 201B, 200C, 201C), which must be taken here.
Very few if any students follow this procedure; in practice students have enough UCLA courses to fulfill the requirements.