Do most students elect to study abroad for a single semester (rather than a full year)?
From my experience studying abroad, most students do choose one semester rather than an entire year. Most students fear that they will not get enough units to graduate on time or that the classes will not count towards their major(s). However, as a language major, I studied abroad for only a semester and wished that I studied abroad for an entire year. The longer you live in a foreign country, the more proficient you become at the language. Also, at a school like UCLA, the French and Francophone Studies department will definitely count all of the classes you take while abroad towards the language major. Most programs are not as flexible, and you will have to look into that.
Studying abroad is about personal growth and learning to adapt to a foreign culture while attending a renowned institution abroad. The longer you immerse yourself in the culture, the more successful the transformation and learning process will be.
Here is the link for the UCLA Study Abroad Office (EAP):http://www.ieo.ucla.edu/eap/