Fill in the missing letters in the paragraph.
The number of underlines shows how many letters you need to fill in. You may answer with the full word or only the missing part.
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In early child_ _ _ _ , thinking abilities change rapidly as children interact with their surr_ _ _ _ _ _ _ _ . Through play, observation, and conversation, they gradually fo_ _ mental models of how the world works. One important milestone occurs when children realize that objects continue to exist even when they are no lon_ _ _ visible. Before reaching this stage, inf_ _ _ _ often behave as i_ a hidden object has completely disa_ _ _ _ _ _ _ . As their understanding grows, however, they begin to search for things that are temporarily o_ _ of sight. This developing understanding is known as object permanence. For psychologists studying early cognition, the emer_ _ _ _ _ %BLANK of object permanence provides an important indicator of intellectual development.