If you look up ugly in an English-French dictionary, you’ll find (amongst a few other adjectives):
laid (m.) and
As an approximation, the feminine form laide sounds like the English word led; the masculine form laid sounds like led without the d on the end.
But there’s also another way to say ugly, which can be heard in colloquial language: laitte (also spelled laite), which sounds like the English word let.
Y’est ben laitte, ton dessin!
Your drawing’s really ugly!
Y’est is a contraction of il est; it sounds like yé. Ben is a contraction of bien; it sounds like the French word bain. Ben means really here.
T’es don’ ben laitte!
You’re so ugly!
T’es is a contraction of tu es; it sounds like té. Don’ is a phonetic spelling of donc, where the c is silent. Don’ and ben together before an adjective is stronger than just ben on its own. (It’s also possible to just say t’es ben laitte, of course.)
C’est trop laitte comme nom!
That’s such an ugly name!
We also saw an example of laitte in a past post. An author said that, on the sidewalks of Québec during moving season, there’s plein de vieux divans à motifs laittes (lots of old sofas with ugly designs).
Remember, laitte is a colloquial form. It’s fine during informal conversations, but not on your French exam (not unless, of course, you’re writing informal dialogue or otherwise know what you’re doing such that you can break the rules).