Page 473 - Practical English Usage 3ed - Michael Swan, Oxford

only thinking about the past: simple past
Shakespeare probably learnt Italian.
THOUGHTS
present perfect (2): perfect or past? 456
thinking about the past and present together: present perfect My sister has learnt French. (= She can speak French naw.)
THOUGHTS
2 finished-time words: present perfect not used
We do not often use the present perfect with words that refer to a completely finished period of time, like yesterday, last week, then, when, three years ago, in 1970. This is because the present perfect focuses on the present, and words like these focus on the past, so they contradict each other. Compare:
- Have you seen Lucy anywhere?
I saw Lucy yesterday. (NOT .' Mile seen Lrtey yesterday.)
- Tom has hurt his leg; he can't walk.
Tom hurt his leg last week. (NOT Tom .'tm hftFt his leg letst week.)
- What have you done with the car keys? I can't find them. What did you do then? (NOT Ylhat Ittllle 16ft dtJne then?)
- My brother has had an accident. He's in hospital.
When did the accident happen? (NOT When htl3 t.'te tteeitlent :'t«fIt'enetl?)
- All my friends have moved to London.
Eric moved three years ago. (NOT Erie M:s mBlled three yett's agB.)
For lenses with just and just now, see 307.
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