Sponge will be having some tiny pores filled with air  yet we are able to compress it

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A sponge has minute holes,in which air is trapped, when we press it,the air is expelled out and we are able to compress it. Sponge is a porous solid but in other words the property of compressibility means an object is compressed and it remains in that compressed shape until we apply force to get it back to its normal position and when we compress sponge it comes back to its original shape automatically in a minute or two.
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