Time Expressions Cheat Sheet: For, Since, Ago, Already, Yet, Just, Still

You can know every tense rule and still lose points on seven tiny words. I have met her two years ago sounds wrong, and so does Have you finished already? when you meant a neutral question. Each of these words acts like a magnet: it pulls a specific tense towards it, and it likes a specific spot in the sentence.

Use this page as a cheat sheet. Start with the master table, then read the three "duels" for the words that get confused most.

The master table

Duel 1: For vs since

Both measure time up to now. The only question is what comes after the word.

• For + length: for three hours, for a week, for ages
• Since + starting point: since 9 a.m., since Monday, since I got here

I've worked here for five years. = I've worked here since 2021. It's the same fact, said two ways.

The trap: I've worked here since five years. → I've worked here for five years.

Duel 2: Already, yet and still

These three all describe where something stands compared with an expectation.

• Already (positive): it's done. She's already left. Often it carries a little surprise: Already? That was quick!
• Yet (negative or question): it's expected but not done so far. Has she left yet? / She hasn't left yet.
• Still (ongoing): it hasn't changed. She's still here.

Mood check. I haven't called him yet is neutral. I still haven't called him adds feeling: I'm surprised, guilty or frustrated that it's taking so long. Notice that still moves in front of haven't.

The trap: I haven't finished already. → I haven't finished yet.

Duel 3: Ago vs for vs just

• Ago looks back from now to a finished moment. It needs the past simple: We met three years ago.
• For talks about a stretch of time that includes now. It takes the present perfect: We've known each other for three years.
• Just means a moment ago: I've just seen him.

The trap: I have seen him two days ago. → I saw him two days ago. Or: I haven't seen him for two days.

A regional note. In British English, just usually goes with the present perfect (I've just arrived). In American English, the past simple is common too (I just arrived). Both are correct. For an exam, the present perfect is the safer choice.

Where does it go in the sentence?

A quick position map:

• Before the main verb: already, just, still, always, never. I've just finished. She still lives there.
• After the verb be: She is still here. He was already asleep.
• At the end: yet, ago and, optionally, already. I haven't seen it yet. It happened a week ago.
• For and since introduce a phrase and are never moved apart from it: for a week and since Tuesday travel together.

Fix-it clinic

• I live here since 2020. → I've lived here since 2020. (Since needs a perfect tense.)
• I've finished my homework two hours ago. → I finished my homework two hours ago. (Ago needs the past simple.)
• Have you already seen the film? is possible for surprise, but the neutral question is → Have you seen the film yet?
• I didn't eat yet. → I haven't eaten yet. (In American English I didn't eat yet is heard, but exams expect the present perfect.)
• She is working here for a year. → She has been working here for a year.

Quick self-check

Choose the right word, then read the answers below the list.

1. I've known him ___ 2018. (for / since)
2. We moved here three years ___. (ago / for)
3. Has the train arrived ___? (already / yet)
4. I'm ___ waiting for my order; it's been an hour! (just / still)
5. She ___ left, so you can't catch her. (just / ago)

Answers: 1. since. 2. ago. 3. yet. 4. still. 5. just.

If you missed two or more, go back to the master table and reread the duel for those words.

Practice it

These words appear in almost every present perfect exercise, so the fastest way to learn them is to practise the tense itself. See present perfect vs past simple for the bigger picture, present perfect vs present perfect continuous for for and since with ongoing actions, and stative verbs explained for why some verbs can't take the continuous form. All of them are part of the full tenses chart.

Practice Present Perfect →