こそFor sure, For certain, Even more so, Underlined or bolded text

より expresses a general comparison, like 'more than (A)' or '~er,' e.g. 月曜日より水曜日がいい ('Wednesday is better than Monday.') or 走るより野球をするのが好き ('I prefer playing baseball to running.'). In contrast, こそ adds emphasis, highlighting something as especially important, e.g. 月曜日こそ図書館に行きたい ('Monday is precisely when I want to go to the library.').

Both structures single out and highlight something, but in different ways. のはXの方だ highlights contrast between options and is often used in apologies, e.g. 悪いのは僕の方だ ('I'm the one that's at fault.') こそ emphasizes exclusivity or importance, e.g. 私こそ謝るべきだ ('I, and no one else, should apologize.')

Both add emphasis, but with opposite nuance. なんか・なんて often downplays or dismisses, while こそ highlights importance or exclusivity. The former can feel self-deprecating or casual, while the latter stresses that something uniquely applies. Compare 私なんかできるのかな？ ('I wonder if someone like me could do it?') versus 彼こそできる ('Him, if no one else, can do it.')

Both use こそ for emphasis, but からこそ highlights a reason or cause, meaning 'precisely because', e.g. 努力したからこそできた ('I could do it precisely because I worked hard.'). こそ on its own emphasizes the word it follows, framing it as precisely the one, e.g. 彼こそできる ('He, if no one else, can do it.')

Both involve the same こそ, but one attaches to nouns and the other to verb + て form. こそ emphasizes a specific word or element, often to contrast or highlight, e.g. 彼こそできる ('He, if nobody else, can do it.'). In contrast, ～てこそ focuses a condition that must be met for something to be true, e.g. 大人になってこそ分かる 'understand only after becoming an adult'.

こそ and なら can look similar after a noun, e.g. 彼こそできる vs. 彼ならできる, but differ in nuance. こそ is emphatic, suggesting that something someone is 'the one', e.g. 彼こそできる ('He's exactly the one who can do it.'). なら implies a conditional focus, e.g. 彼ならできる ('If it's him we're talking about, he can do it.'), without the nuance of excluding other possibilities that こそ can have.

Both express emphasis, but in different ways. あまり is a noun that emphasizes an extreme degree leading to an unintended result, e.g. 悲しみのあまり泣き出した ('She burst into tears from too much sadness.') こそ is a particle that stresses importance or exclusivity, e.g. 今日こそ早く寝よう ('Today, for sure, I'll go to bed early.')