Vow & show the result
declare “I’ll do it and prove it”
Open details
Form: V-て + みせる
Use when: you promise to accomplish A and demonstrate it to others.
Contrast: simple plan → 〜つもりだ (no “prove it” nuance).
Mini example
必ず
I will deliver results—just watch.
Even by tough means
achieve the goal even if method is hard
Open details
Form: V-て + でも
Use when: you will do B even if A (a hard/undesirable step) is required.
Contrast: excessive action → see 〜てまで.
Mini example
I’ll meet the deadline even if I must work all night.
Go so far as to… (often too far)
criticism about excessive method
Open details
Form: V-て + まで + V ／ N + までして + V
Use when: judge that the method is excessive for the purpose.
Avoid: praising with it; it often carries a negative tone.
Mini example
There’s no need to get the contract by even breaking rules.
No choice but to ~ (formal)
action is forced by circumstances
Open details
Form: V-ない (drop ない) + ざるを得ない ／ する→せざるを得ない
Use when: you must do it; outside pressure leaves no option.
Contrast: neutral “only option” → 〜しかない.
Mini example
Given the circumstances, we have no choice but to raise prices.
Can’t stay as is; must act
urge to move from current state
Open details
Form: V-て + はいられない（= can’t keep doing V）
Use when: you must switch to action instead of staying passive.
Avoid: future long-term plans; it’s for “right now” pressure.
Mini example
こうしてはいられない。すぐ
We can’t sit here—let’s start preparations now.
Now that X is true → resolve
commitment follows a fact/decision
Open details
Form: V-plain + 上は ／ N + である + 上は
Use when: once A is decided/known, B (duty/resolve) naturally follows.
Contrast: purpose “for doing” → 〜上で（目的） (different grammar).
Mini example
Now that I’ve decided to join, I’ll prepare with full effort.
Worth the effort / in vain
evaluate results after trying
Open details
Form: (V-た / N の) + かいがあって ／ (V-た / N の) + かいもなく
Use when: praise or lament the outcome of your effort.
Contrast: “worth it” noun → 〜の甲斐 (same word family).
Mini example
Thanks to the practice, the presentation was a great success.
Strong “will not” / “probably not”
written / serious tone
Open details
Form: V-dictionary + まい（する→するまい／しまい）
Use when: firm decision not to do / or conjecture “probably not”.
Contrast: everyday speech → “もうV-ないだろう／V-しない”.
Mini example
もう
I will never make a rash decision again.
1) 〜てみせる — vow & demonstrate
Declare a strong promise and the intention to show the result to others.
Form: V-て + みせる Tone: determined, motivating.
次こそ 合格 してみせる。
I’ll pass next time—watch me.
I will turn this division around.
I’ll put my parents at ease.
2) 〜てでも — even by tough means
You will reach the goal even if you must take a hard or undesirable step.
Form: V-て + でも Nuance: strong resolve for the goal.
I’ll finish this proposal even if I have to stay up all night.
I want to study abroad even if I must borrow money.
少しの 赤字 を 出してでも 顧客 を 守る。
We’ll protect our customers even at a small loss.
3) 〜てまで・〜までして — go so far as to… (often excessive)
Used to criticize an excessive method for a goal.
Form: V-て + まで + V ／ N + までして + V
You shouldn’t protect your reputation to the point of lying.
ルール 違反 までして 勝 つ 価値 は ない。
Winning isn’t worth breaking the rules.
Let’s not watch videos to the point of pulling an all-nighter.
4) 〜ざるを得ない — have no choice but to ~ (formal)
A formal expression used when circumstances force the action.
Form: V-ない (drop ない) + ざるを得ない ／ する→せざるを得ない
Due to bad weather, we had to postpone.
Costs have risen, so we must raise prices.
その 提案 は 受 け入れざるを得ない。
We have no choice but to accept the proposal.
5) 〜てはいられない — can’t keep ~; must act
You cannot stay in the current state; immediate action is needed.
Form: V-て + はいられない ／ common: 〜てばかりはいられない
いつまでも 落 ち込 んでいてはいられない。
I can’t stay depressed forever.
We can’t keep complaining; let’s plan countermeasures.
こうしてはいられない。すぐ 出発 しよう。
We can’t sit here—let’s head out now.
6) 〜上は — now that …, I must ~
Once a fact/decision is set, a duty or firm action naturally follows.
Form: V-plain + 上は ／ N + である + 上は Register: formal resolve.
Now that I’ve decided to take the exam, I’ll give it my all.
リーダーに 選 ばれた 上は、責任 を 果 たす。
Since I was chosen as leader, I must fulfill my duties.
ここまで 来た 上は、最後 まで やり抜 く。
Now that we’ve come this far, we’ll see it through.
7) 〜かいがあって / 〜かいもなく — effort paid off / in vain
Evaluate results after putting in effort: success vs. no return.
Form: (V-た / N の) + かいがあって ／ (V-た / N の) + かいもなく
Our practice paid off—we won.
1時間 並んだ かいがあって、限定 商品 を 買 えた。
It was worth queueing an hour—we got the limited item.
The surgery was in vain; the symptoms worsened.
8) 〜まい — strong “will not” / “probably not” (written)
A firm decision not to do something, or a guess that something will not happen. Serious, written tone.
Form: V-dictionary + まい（する→するまい／しまい） Variant: V-まい + と + V（try not to ~）
もう 軽率 な 言 い方 は するまい。
I will not speak carelessly again.
かれは 戻 るまい。
He probably won’t come back.
I tried not to cry, but tears fell.
Quick contrasts & pitfalls
- 〜てでも vs 〜てまで: the first = strong resolve (“even if I must …”), the second = often a negative judgment (“going too far”).
- 〜ざるを得ない vs 〜しかない: both mean “no choice,” but ざるを得ない is more formal/official.
- 〜てはいられない shows urgency “now”; don’t use it for distant future plans.
- 〜上は follows a fixed fact/decision; it leads to duty or commitment.
- 〜まい is written/serious. In daily talk, say “もうVしない” (intention) or “Vないだろう” (conjecture).
