Past Simple: Time expressions

Most time expressions go at the end of a sentence. This is the most common and natural spot. You can also put them at the start of a sentence. Putting them at the start adds a bit of drama or emphasis. It highlights the "when" rather than the "what." For example, "I saw a movie yesterday" is a standard fact. "Yesterday, I saw a movie" sounds like you are starting an exciting story. Just remember that these words only work with finished time. If the time period is still happening, we usually use different grammar. Think of it like a closed book. Once the day or year is over, it belongs to the Past Simple. It is a simple relationship: finished action plus finished time equals Past Simple.

1. 1The Ago Rule: Place the amount of time first, then add ago at the end.
2. 2ten minutes + ago = ten minutes ago.
3. 3three years + ago = three years ago.
4. 4The Last Rule: Place last before the specific time period or day.
5. 5last + night = last night.
6. 6last + Friday = last Friday.
7. 7The In Rule: Use in for specific years, months, or centuries.
8. 8in + 1998 = in 1998.
9. 9in + July = in July.
10. 10The Yesterday Rule: Use yesterday for the day before today.
11. 11You can combine it: yesterday morning, yesterday afternoon.
12. 12The On Rule: Use on for specific calendar dates or days of the week.
13. 13on + Monday = on Monday.
14. 14on + October 4th = on October 4th.

Use these expressions when you have a specific point in time. This is very helpful in real-world scenarios.

• Job Interviews: You might say, "I finished my degree in 2020." This shows you are precise and professional.
• Ordering Food: "I had this dish last week and it was amazing!"
• Travel Stories: "We arrived in Rome four days ago." It helps your friends visualize your trip.
• Excuses: "I sent that report yesterday afternoon, please check your inbox."
• Asking Directions: "The bus left five minutes ago, you just missed it!"

If you can point to the moment on a calendar or a clock, use these expressions. They are perfect for anything that is 100% over. It is like a grammar traffic light that has turned red; the action has stopped.

Do not use these specific time expressions with the word have or has. This is a very common trap.

• ✗ "I have seen him yesterday." (This sounds very strange to native speakers).
• ✓ "I saw him yesterday."

Also, avoid using last with the word day. We have a special word for that: yesterday.

• ✗ "I went to the gym last day."
• ✓ "I went to the gym yesterday."

Do not use ago for things that are still happening now. Ago always looks backward from the current moment. It is like looking in a rearview mirror. If you are still in the middle of the action, ago is not your friend.

A very frequent mistake is using since instead of ago.

• ✗ "I moved here since three years."
• ✓ "I moved here three years ago."

Since needs a specific starting point, while ago measures the distance back from now. Another tricky one is last night. Many learners want to say yesterday night. While people will understand you, it sounds a bit "off." Stick to last night to sound like a pro. Also, watch out for the word in. You don't need it with last.

• ✗ "I traveled in last summer."
• ✓ "I traveled last summer."

Yes, even native speakers mess this up when they are tired, but you can be better! Think of these rules as the secret sauce to your past tense sentences.

Compare these two sentences: "I lived in London" and "I lived in London in 2015." The first sentence is a general fact about your life. The second sentence is a specific memory tied to a date. Adding the time expression makes the sentence feel more "complete." Now, compare Past Simple with Present Perfect. "I have eaten" means your stomach is full right now. "I ate an hour ago" is just a fact about the past. The Past Simple with a time expression is like a finished stamp on a document. Once you add ago or last, the door to the present is locked and bolted. It is all about that specific, finished moment.