Here are some negative expressions in French.

ne...pas
(not)
e.g. je n'amie pas (I don't like, I am not liking)
ne...jamais
(never)
e.g. je n'ai jamais redoublé (I have never retaken a year)
ne...personne
(nobody, no-one, not anybody)
e.g. Je n'ai vu personne ( I have seen nobody, I didn't see anybody).

To say; ….not, or not…., on it's own, say ….pas, or pas…..

Here are some comparative expressions

aussi...que
(as...as)
e.g. aussi dur que (as hard as)
plus...que
(more...than, ...er)
e.g. plus grand que (more big than, bigger than)
moins...que
(less...than)
e.g. moins difficle que (less difficult than)
meilleur que...
(better than...)
le/la/les plus…
(the most…, the ...est)
e.g. la/le/les plus grand(e)(s) (the biggest)
le/la/les meilleur(e)(s)
(the best)