Pleasant, splendid, or attractive; used to praise something (na-adjective).
この庭は結構ですね。
This garden is lovely.
あのレストランは雰囲気も料理も結構で評判がいい。
That restaurant has a great atmosphere and food, and it's well regarded.
先生は彼の発表を結構だと褒めた。
The teacher praised his presentation as excellent.
Sufficient or satisfactory; enough. Often used to indicate that something is enough (e.g. 'No, thank you').
コーヒーはいりません、結構です。
No coffee for me, thanks. / I'm fine (without it).
予算はこれで結構です。
This budget is sufficient.
もう結構です、と彼は丁寧に断った。
He politely declined, saying 'No, thank you.'
Used to indicate you do not want any more or want something to stop ('that's enough').
その冗談はもう結構だ。やめてくれ。
That's enough of that joke. Please stop.
プレゼントは十分ありますから、もう結構です。
I already have enough presents, so that's enough.
彼は気を使って何度も頼んだが、彼女は『結構です』と断った。
He asked several times out of politeness, but she declined, saying 'No, thank you.'
An adverb meaning 'quite', 'fairly', or 'rather' (e.g. 'quite expensive'). Frequently used in speech.
この寿司は結構高いよ。
These sushi are pretty expensive.
彼は結構日本語が話せる。
He can speak Japanese quite well.
今日は結構疲れたから早く寝る。
I'm fairly tired today, so I'll go to bed early.
The structure or construction of something (architectural or structural); somewhat literary/technical—modern Japanese more commonly uses '構造'.
古い橋の結構を調べるために現地調査を行った。
We conducted an on-site survey to examine the structure of the old bridge.
家屋の結構がしっかりしていると地震に強い。
A house with a solid structure is resistant to earthquakes.