In short

This set turns the volume up or down on one word in the sentence. こそ koso points at something and says “this one and no other” (今度こそ kondo koso, “this time for sure”); さえ／すら sae / sura say “even” and pick the most surprising case (子供さえ知っています, “even children know it”); にすぎない ni suginai deflates something to “no more than that”; だけあって dake atte credits a result to the thing that explains it. They are the escalatory, register-marked cousins of the everyday だけ／しか／ばかり you learned in lesson 34.

The rule

Everything here is a 取り立て toritate device - it picks one element out of the sentence and comments on it. That means two practical things: it goes after the word it highlights, and it usually replaces が and を while leaving に, で, から, と in place.

Step 1 - こそ: “this, precisely.” Put こそ after a noun to identify it emphatically. これこそ本物です。 (Kore koso honmono desu.) - “This is the genuine article.” が and を drop out (×これがこそ), but other particles survive and こそ follows them: 今こそ ima koso (“now is the moment”), ここでこそ koko de koso.

Three frozen uses carry most of the everyday load:

• こちらこそ kochira koso - “no, I am the one who should say that”, the standard reply to thanks or an apology.
• 今度こそ kondo koso - “this time for sure”, after previous failures.
• 〜からこそ - precisely because. Attach it to the plain form plus から; the sentence very often closes with 〜のです／〜んです, though it need not (忙しいからこそ、家族との時間を大切にしたいです): 好きだからこそ、厳しく言うのです。 (Suki da kara koso, kibishiku iu no desu.) - “It is exactly because I like you that I speak strictly.” Plain から states a reason; からこそ insists that this reason, and no rival reason, is the true one.

〜ばこそ is the same idea in stiff written Japanese: the ば-form + こそ, again ending in のだ. 親が子を思えばこそ、厳しくするのです。 (Oya ga ko o omoeba koso, kibishiku suru no desu.) Recognise it; you rarely need to produce it.

Step 2 - こそ as a concession frame: “admittedly X, but…” Put こそ on a noun and follow the clause with が／けれど, and the sentence concedes that one point while overturning it: 値段こそ高いですが、品質は確かです。 (Nedan koso takai desu ga, hinshitsu wa tashika desu.) - “The price, admittedly, is high, but the quality is dependable.” The everyday equivalent repeats the word instead - 高いことは高いですが - and the formal literary version uses the ます-stem + こそすれ: 増えこそすれ、減ることはありません (“it may well rise, but it will not fall”).

Step 3 - さえ／すら: “even”, the extreme case. さえ after a noun means “even this one, so certainly all the rest”: その漢字は子供さえ知っています。 (Sono kanji wa kodomo sae shitte imasu.) In practice でさえ is even more common for people and things acting as subjects (子供でさえ), and negative sentences are its natural home: 名前さえ書けませんでした (“couldn’t even write his name”). すら is the same meaning in a stiffer, written register - swap it in for さえ in an essay or a report, never in chat.

Step 4 - まで: “even, going so far as.” Where さえ picks a surprising member of a set, まで marks how far an action was pushed along a scale - and it behaves like こそ and さえ on the particles in front of it: に, で, から and と stay, while が and を drop (親にまで, but 嘘までつきました): 親にまで嘘をつきました。 (Oya ni made uso o tsukimashita.) - “He lied even to his own parents.” This is the emphatic まで, not the “up to” まで of lesson 6.

Step 5 - さえ〜ば: “if only”, a different pattern entirely. Do not confuse this with “even”. Here さえ marks the one condition that is enough, and the predicate takes the ば-form - と is impossible here, and たら only turns up colloquially: お金さえあれば、何でも買えます。 (Okane sae areba, nan demo kaemasu.) - “If only I had money, I could buy anything.” With a verb, さえ slides in after the ます-stem and する carries the ば: 読みさえすれば分かります (yomi sae sureba wakarimasu). See the paradigm table below - the joins are where marks are lost.

Step 6 - にすぎない: “no more than.” Attach にすぎない (polite にすぎません) to a noun, a quantity or a plain-form clause to deflate it: それはうわさにすぎません。 (Sore wa uwasa ni sugimasen.) - “That is nothing but a rumour.” 十パーセントにすぎません - “a mere ten per cent.” It always downgrades, so it pairs naturally with ただの (“mere”): ただの言い訳にすぎません (tada no iiwake ni sugimasen, “merely an excuse”).

Step 7 - だけあって／だけに／だけのことはある: the earned result. These say “as you would expect from X” - X justifies the result. Attachment is the plain form, with な after a na-adjective and nothing (or である) after a noun. さすが元プロだけあって、教え方が上手です。 (Sasuga moto puro dake atte, oshiekata ga jōzu desu.) The adverb さすが often introduces them.

The caution: だけに does the same job but is not restricted to good news - it also intensifies a disappointment, and then the second clause is negative in feeling: 期待していただけに、残念でした。 (Kitai shite ita dake ni, zannen deshita.) - “Precisely because I had had hopes, it was disappointing.” 〜だけのことはある closes a sentence as a verdict: 高いだけのことはあります。 (“It is worth the price.”)

Step 8 - のみ／のみならず and ばかりか／どころか. のみ is the formal, written だけ: 会員のみ入場できます (kaiin nomi nyūjō dekimasu, “members only”). のみならず is the formal だけでなく, and the second clause normally carries も: 英語のみならず、フランス語も話せます。 ばかりか is its ordinary-register twin and adds surprise - the second item outdoes the first.

どころか is the one to slow down for, because it has two readings and both deny the first element:

1. “Far from X - the opposite is true.” 彼は謝るどころか、笑っていました。 (Kare wa ayamaru dokoro ka, waratte imashita.) - “Far from apologising, he was laughing.”
2. “Let alone X - not even the smaller thing.” Here the second clause is negative and takes も: 漢字どころか、ひらがなも読めません。 - “Let alone kanji, he can’t even read hiragana.”

Ordering against lesson 34. だけ, しか〜ない and ばかり are quantitative and everyday: they count and they belong in speech. This set is escalatory and register-marked: こそ and さえ dramatise, のみ and すら are written Japanese, にすぎない and だけあって pass judgement. Same slot in the sentence, different job and different register.

Forms & patterns

Emphasis - what each one attaches to:

さえ has two unrelated jobs - the second one needs the ば-form:

Limitation and judgement:

Examples

Common mistakes

• これがこそ本物です。 (Kore ga koso honmono desu.) -> これこそ本物です。 (Kore koso honmono desu.) - が and を drop in front of こそ, exactly as they do in front of しか. に, で, から and と stay: 今こそ, ここでこそ.
• お金さえあったら、何でも買えます。 (Okane sae attara, nan demo kaemasu.) -> お金さえあれば、何でも買えます。 (Okane sae areba, nan demo kaemasu.) - the “if only” frame is built with the ば-form. たら is heard in casual speech but is not the form to produce, and と does not work here at all.
• 読むさえすれば分かります。 (Yomu sae sureba wakarimasu.) -> 読みさえすれば分かります。 (Yomi sae sureba wakarimasu.) - with a verb, さえ is inserted after the ます-stem and する takes the ば ending.
• 有名だけあって、人が多いです。 (Yūmei dake atte, hito ga ōi desu.) -> 有名なだけあって、人が多いです。 (Yūmei na dake atte, hito ga ōi desu.) - a na-adjective keeps its な in front of だけ, as it does before こと and ので.
• 漢字どころか、ひらがなも読めます。 (Kanji dokoro ka, hiragana mo yomemasu.) -> 漢字どころか、ひらがなも読めません。 (Kanji dokoro ka, hiragana mo yomemasen.) - in the “let alone” reading the second clause must be negative; a positive one produces the opposite claim.

Tips

• こそ answers an unspoken “which one?” If you could say “no, this one” or “this time, unlike last time”, こそ fits. If you simply want to add force to a whole sentence, use an adverb (本当に, ぜひ) instead - こそ always narrows onto a single element.
• Read さえ backwards to check it. “Even X” implies “so obviously everything above X too”: 子供さえ知っている means adults certainly do. If that inference does not hold, you want も or だけ, not さえ.
• さえ appears in two patterns that share nothing. さえ alone = “even” (a fact); さえ + ば = “if only” (a condition). The ば-form at the end of the clause is your only reliable signal - watch for it before you translate.
• Sort the register before you write. In an essay: のみ, のみならず, すら, にすぎない, ばこそ. In conversation: だけ, だけでなく, さえ, こそ, ばかりか. Mixing them - のみ in a chat message, だけ in a formal report - is the giveaway of writing assembled from a grammar list.