しかないHave no choice but to
Use this when circumstances leave only one realistic course of action. It often conveys practical necessity or reluctant resignation: “there is nothing to do but…”
How it works
The verb names the sole remaining action. The speaker has considered the situation and concluded that the other possibilities are unavailable, impractical, or already exhausted. English often uses “have no choice but to” or “will just have to”; a simple “must” may also work when the context makes the lack of alternatives clear.
The only practical option
The surrounding context normally shows why the alternatives have disappeared.
終電がもう出てしまったので、タクシーで帰るしかない。
The last train has already left, so we have no choice but to take a taxi home.
Analyze予算を増やせないなら、計画を縮小するしかない。
If we cannot increase the budget, we will have to scale back the plan.
Analyzeほかの店も閉まっているし、ここで食べるしかないね。
The other restaurants are closed too, so I guess we'll just have to eat here.
AnalyzeThe sentence-ending particle softens the resigned conclusion and invites agreement.
Choosing among similar expressions
しかない presents an action as the only viable option. By contrast, だけ simply limits something and does not itself say that circumstances force a particular action. よりほかない and より仕方がない give a similar no-alternative conclusion in a more formal style. ざるを得ない more strongly emphasizes being compelled to act despite reluctance.
More examples
電車が止まっているので、歩いて行くしかない。
The trains are not running, so we have no choice but to walk.
Analyze予約が全部埋まっている。来週まで待つしかない。
All the appointments are booked. I'll just have to wait until next week.
Analyze財布をなくしたので、すぐにカードを止めるしかない。
I lost my wallet, so I have no choice but to cancel my cards immediately.
Analyzeこの道が通れないなら、遠回りするしかない。
If this road is impassable, we'll have to take the long way around.
Analyze誰も引き受けてくれないなら、私がやるしかない。
If no one else will take it on, I have no choice but to do it myself.
Analyzeパソコンが壊れて修理もできないから、新しいものを買うしかない。
The computer is broken and cannot be repaired, so I'll have to buy a new one.
Analyze