Use the Simple Past when the action happened at a finished time in the past.

Ask yourself: When did it happen? If you can answer with a finished time (yesterday, last year, in 2020, two hours ago), use the Simple Past.

Subject + past tense verb

• I visited Boston.
• She bought a new phone.
• They arrived late.

Common time expressions

• yesterday
• last week/month/year
• in 2018
• two days ago
• this morning (if the morning is over)
• when I was a child

Examples

• I saw that movie yesterday.
• We met in 2022.
• She finished her homework an hour ago.

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Use the Present Perfect when the exact time is not important or the action has a connection to the present.

Ask yourself: Is the result or experience important now? If yes, use the Present Perfect.

Subject + have/has + past participle

• I have visited Boston.
• She has bought a new phone.
• They have arrived.

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The Four Main Uses of the Present Perfect

1️⃣ The time doesn’t matter.

• I have been to Japan.
• She has never ridden a horse.
• Have you ever eaten sushi?

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2️⃣ An Action That Happened Recently

Usually with:	Examples:
just	I’ve just finished.
already	She’s already left.
yet	Have you eaten yet?

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3️⃣ An Action That Started in the Past and Continues Now ( The action is still true now. )

Often with:	Examples:
for	I have lived here for ten years.
since	She has worked here since 2020.

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4️⃣ A Past Action with a Present Result

Examples:

• I’ve lost my keys.
  (I don’t have them now.)
• She’s broken her leg.
  (Her leg is still broken.)
• We’ve missed the bus.
  (We’re still waiting.)

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The Golden Rule

Simple Past = Finished Time

When did it happen?

• yesterday
• last week
• in 2015
• two hours ago

Present Perfect = Unfinished Time or Present Connection

Has it happened before now?

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Compare the Difference

Example one:

Simple Past	Present Perfect
I lost my keys yesterday.	I’ve lost my keys.
(The time is important.)	(The result is important—I can’t find them.)

Example two:

Simple Past	Present Perfect
Did you eat breakfast this morning?	Have you eaten breakfast today?
(The morning is finished.)	(Today is not finished.)

Example three:

Simple Past	Present Perfect
She worked here from 2018 to 2022.	She has worked here since 2018.
(She doesn’t work here anymore.)	(She still works here.)

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Signal Words

Simple Past	Present Perfect
yesterday	ever
last…	never
ago	already
in ( 2010 )	yet
when I was…	just
then	since
before	for
after	recently
If you see one of these, the Simple Past is almost always correct.	lately
	so far
	up to now
	this week (if the week isn’t over)
	today (if today isn’t over)