招く vs the swamp kanji is ruining me

so 招く is to invite right like the waving cat. but i keep writing 沼く which is swamp and now i told my host family i wanted to swamp them to dinner. also pronunciation tip!! its pronounced exactly like money-cue but without the y. moneycue. anyway then i saw 紹 for introduce and i actually threw my notebook. they all look like the same little guy doing a dance. help