Present Perfect and Past Simple

Present Perfect and Past Simple

Present Perfect Simple	Past Simple
Unfinished actions that started in the past and continue to the present: I've known Julie for ten years (and I still know her).	Finished actions: I knew Julie for ten years (but then she moved away and we lost touch).
A finished action in someone's life (when the person is still alive: life experience): My brother has been to Mexico three times.	A finished action in someone's life (when the person is dead): My great-grandmother went to Mexico three times.
A finished action with a result in the present: I've lost my keys! (The result is that I can't get into my house now).	A finished action with no result in the present: I lost my keys yesterday. It was terrible! (Now there is no result. I got new keys yesterday).
With an unfinished time word (this week, this month, today): I've seen John this week.	With a finished time word (last week, last month, yesterday): I saw John last week.

 Simple Past

Jenis Kalimat	Rumus	Contoh Simple Past Tense
positif (+)	S + Verb-2 (past tense) S + be(was/were)	The teacher came
		I was a stamp collector
negatif (-)	S + did + not + bare infinitive S + be(was/were) + not	The teacher didn’t come
		I wasn’t a stamp collector
interogatif (?)	Did + S + bare infinitive be(was/were) + S	Did the teacher come
		Was I a stamp collector

  

 Present Perfect

kalimat	Rumus	Contoh Present Perfect Tense
positif (+)	S + aux. verb(have/has) + V-3/past participle	I have read the book
		He has left
negatif (-)	S + aux. verb(have/has) + not + V-3/past participle	I have not read the book
		He hasn’t left
interogatif (?)	aux. verb(have/has) + S + V-3/past participle	Have I read the book
		Has he left

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