passive/potential ambiguity

For ru-verbs (建てる, 食べる, 見る, 着る), the passive form and potential form are morphologically identical — 建てられる, 食べられる, 見られる, 着られる. Context alone disambiguates 'be V-ed' from 'can V.' (U-verbs avoid this collision via the dedicated potential 書ける, 飲める, 行ける.) Some speakers use the 'ら抜き' form 見れる / 食べれる to force the potential reading and avoid ambiguity, though this remains stigmatized in formal contexts.