Both yet and already are connected to expectations. When you use either word, you are measuring the real world against what was expected to happen. The difference between them is about which side of that expectation you are standing on.
Already says: something happened sooner than expected — before I thought it would, or before I had a chance to mention it.
Yet says: something has not happened but was expected — it should have happened by now, but it hasn't.
Think of a race between reality and expectation. Already means reality crossed the finish line first. Yet means reality hasn't crossed it, but we expected it to.
Already expresses mild surprise or emphasis that something has happened — often sooner than the speaker expected, or before any action was needed. It goes between have/has and the past participle, or occasionally at the end of the sentence for extra emphasis.
Already can also be used in questions to express surprise, or to check whether something has happened sooner than expected:
Yet is used in negative sentences and questions. It refers to something the speaker expects to happen — or expected to have happened by now — but which has not happened. Yet always goes at the end of the sentence.
| ALREADY | YET | |
|---|---|---|
| Meaning | Sooner than expected / already done | Expected but not happened so far |
| Used in | Affirmatives + surprise questions | Negatives + questions |
| Position | Between have/has and the past participle | At the end of the sentence |
| Example | She has already left. | She hasn't left yet. |
| Question | Has she already left? (surprise) | Has she left yet? (checking) |
✗ She has yet left. · I have yet finished. · He has yet eaten.
✓ She has already left. · I have already finished. · He has already eaten.
Yet is not used in standard affirmative sentences. In affirmative sentences, use already. The one formal exception is the phrase have yet to (= still have not done), which is more advanced and rare: I have yet to receive a reply. But in everyday speech and writing, yet belongs only in negatives and questions.
✗ She has left already. (informal/non-standard) · I haven't yet finished. / I haven't yet seen it.
✓ She has already left. (standard — already in the middle)
✓ I haven't finished yet. (yet at the end — standard position)
In standard American English, already goes between have/has and the past participle, and yet goes at the end of the sentence. Placing already at the end or yet in the middle is possible in some dialects and informal registers, but it is not the standard form you should practice. Learn the standard positions and stick to them.
✗ She hasn't replied still. · I haven't finished still.
✓ She still hasn't replied. · I still haven't finished.
✓ She hasn't replied yet. · I haven't finished yet.
Both still and yet can express that something hasn't happened, but they are placed differently. Still goes before the auxiliary: She still hasn't replied. Yet goes at the end: She hasn't replied yet. Never put still at the end of the sentence in a negative.
✗ Did you finish yet? · She already left. · I didn't see it yet.
✓ Have you finished yet? · She has already left. · I haven't seen it yet.
Yet and already are adverbs that belong to the Present Perfect. They describe how an action relates to the current moment — whether it happened sooner than expected or hasn't happened yet. The Past Simple does not have this relationship with the present, so it cannot be used with these adverbs in this meaning. Always pair yet and already with the Present Perfect.