There are some adjectives which look like they should follow the rules from the previous page, but they don’t.

The most often-used of these pseudo-adjectives (“fake” adjectives) is kirei (pretty, beautiful). Another pseudo-adjective is shizuka (quiet). When these adjectives directly modify a noun, you use the particle na:

kireinaie (pretty house)
shizukanahito (quiet person)

Unlike true adjectives, which change their form, pseudo-adjectives never change their forms.

iehakireidesu (The house is pretty.)
iehakireideshita (The house was pretty.)
iehakireidehaarimasen (The house is not pretty.)
iehakireidehaarimasendeshita (The house was not pretty.)

hitohashizukadesu (The person is quiet.)
hitohashizukadeshita (The person was quiet.)
hitohashizukadehaarimasen (The person is not quiet).
hitohashizukadehaarimasendeshita (The person was not quiet.)