成語 with 鮑魚, grammar structure?
如{[(入&lt;鮑魚之肆&gt;)久]而[不(聞&lt;其臭&gt;)]}。
It's like {[(having entered &lt; a market of fish &gt;) for long time] hence [can't (smell &lt; its stink &gt;)]}.

The root level is V-O '如...' (it's like ...), 如 is the verb.
Then 入鮑魚之肆久而不聞其臭 is Phrase-Conj-Phrase '...而...' (... hence ...), where 而 is the conjunction.
入鮑魚之肆久 is S-V, where 入鮑魚之肆 is 'V-O as Subject', 久 is the verb.
In 入鮑魚之肆, 入 is the verb (to enter), 鮑魚之肆 is noun phrase as the Object. 之 means 'of', 鮑魚之肆 means 'market of fishes'.