Meaning of painted

[Garmasch]

ESL/EFL Test "English Grammar Exercise", question 5

All of the walls are ......... white.

(a) paint
(b) painted
(c) to paint
(d) painting

ESL/EFL Test "English Grammar Exercise", answer 5

All of the walls are painted white.

Correct answer: (b) painted

Your answer was: incorrect
All of the walls are paint white.
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why we use painted in this example cause if we use just paint we have the same idea?

[Alan]

Hi Garmasch,

You need painted here because it is the past participle.

Alan
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English as a Second Language
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