mistake

fault / carelessness / oversight / error / negligence / blunder / misstep / accident / mistake

fault / carelessness / oversight / error / negligence / blunder / misstep / accident / mistake

annex / amalgamate / merge

combining / annex / merge *something with *something / annexation / uniting / merger / amalgamate *something with *something / incorporating / incorporate / combine *something with *something / combination / unite *something with *something / merging / amalgamating / union

contemplate / meditate on / be lost in thought

meditation / speculate on / ponder / meditate / consideration / contemplate / meditate on / speculate / muse on / muse / think / consider / contemplation

be lost in thought / contemplate / meditate on

contemplate / meditate on / ponder over

special / temporary / extra / extraordinary