Construction · C2 · Formal or literary · uncommon in ordinary US English
lest
lest A single, crisp stressed syllable.
Meaning
So that something unwanted does not happen; for fear that it might happen.
Srpski
da ne; kako ne bi; iz straha da
Use it
Save a copy lest the original be lost.
Formal subjunctive: be, not is.
She lowered her voice lest anyone should hear.
UK English may use should + base verb; US English normally uses the bare subjunctive.
Build the sentence
main clause + lest + subject + base verb
Save a copylestthe original be lost
Memory scene
Lest is a small verbal guardrail: it appears before the danger you are trying to prevent.
Watch out
Lest already contains a negative idea, so do not add not. It does not mean unless: lest names the feared outcome, not a condition.
Nearby language
closestfor fear that
The clearest close paraphrase.
closestso that … not
More neutral and natural in everyday speech.
differentin case
Related precaution, but it does not always express a feared outcome.
Make it yours
Situacija
Sačuvajte kopiju kako se original ne bi izgubio.
Your task
No automatic grading—compare meaning, grammar, and tone.