飛(ひ)行(こう)機(き) hikoukiは wa雲(くも) kumoの no中(なか) nakaに ni見(み)え()な()く() mienakuなった natta。 The airplane disappeared into the clouds. Literal Airplane [topic-は] clouds [possessive-の] inside [into-に] visible-not became. 見えなくなる combines the potential/spontaneous 見える ('to be visible') with ~なくなる ('cease to'). The plane didn't actively hide — it simply became invisible to the observer as it entered the clouds. weatherairplanestransportation~なくなる (cease to)
飛(ひ)行(こう)機(き) hikoukiは wa雲(くも) kumoの no中(なか) nakaに ni見(み)え()な()く() mienakuなった natta。 The airplane disappeared into the clouds. Literal Airplane [topic-は] clouds [possessive-の] inside [into-に] visible-not became. 見えなくなる combines the potential/spontaneous 見える ('to be visible') with ~なくなる ('cease to'). The plane didn't actively hide — it simply became invisible to the observer as it entered the clouds. weatherairplanestransportation~なくなる (cease to)