Present Perfect используется когда не важно точное время события в важен итог, знания, опыт, информация. Слова-маркеры этого времени: Already - уже, just - только что, yet - еще не, never - никогда, ever - когда-нибудь.
Если есть точное указание на время: yesterday, two days ago, last year и т.п., то надо использовать Present Simple.
1 Grandpa isn’t listening
to the radio; he's asleep in his chair. (not listen)
2 Markspends
quite a few hours a day on Facebook and Twitter. (spend)
3 The boys aren't here. They are watching
the football final on Jack's wide-screen TV. (watch)
4 This satnav system is useless; it only works
some of the time. (work)
5 My brother always borrows
my laptop and it's really annoying! (always / borrow)
6 Are you buying
a Samsung or an iPhone? Have you decided yet? (you/ buy)
7 The tablet I bought on eBay isn't great; it doesn’t stream
videos very well. (not stream)
8 This video takes
ages to download. It's been 30 minutes already. (take)
Объяснение:
1. have already done
2. did
3. has just come
4. came
5. played
6. has already come
7. read
8. have read
9. have never been
10. Have you ever been to New York?
11. Have you ever seen the eruption of volcano?
12. I haven’t eaten today yet.
13. He didn’t eat yesterday.
14. Did you play piano yesterday?
15. Have you played piano today?
Объяснение:
Present Perfect используется когда не важно точное время события в важен итог, знания, опыт, информация. Слова-маркеры этого времени: Already - уже, just - только что, yet - еще не, never - никогда, ever - когда-нибудь.
Если есть точное указание на время: yesterday, two days ago, last year и т.п., то надо использовать Present Simple.