Typically with comparisons, if the adjective in English is just one syllable, you add -er to the end, but if the adjective is more than one syllable, it requires "more" before it.
Examples: She is taller than he is (or smarter, or stronger, or fatter, etc).
but She is more beautiful (or more clever, more industrious, more
sophisticated) than he.
An exception: you can't say "funner" even though "fun" is one syllable. You should say (as an example: Studying languages is more fun that watching TV)