Page 62 - Practical English Usage 3ed - Michael Swan, Oxford

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the difference between ago and for
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Ago says how long before the present something happened; for (with a past tense) says how long it lasted. Compare:
He died three years ago. (= three years before now)
(NOT He dietl/o,. t.'1ree years. OR ••• J'tJr three years ttgB.)
He was ill for three years before he died. (= His illness lasted three years.) ago and before with time expressions: counting back
We use ago with a past tense and a time expression to 'count back' from the present; to say how long before now something happened.
We can use before in the same way (with a past perfect tense) to count back from a past moment (see also 96). Compare:
1 met that woman in Scotland three years ago. (NOT ••• three )'ettrs bejtJte I ~'tJre three yettrs.)
When we got talking, 1found out that 1had been at school with her husband ten years before. (NOT ••• ten yea,s agB.)
ago and before
1 m e t h e r rI,ree y e a r s a g o . 1 h a d b e e n a t s c h o o l w i t h h e r h u s b a n d t e n
years befoTT!.
ten years before three years ago
For other uses of before. see 97-98.
34 alike
The adjective alike means 'like each other'. Compare: The two boys are alike in looks, but not in personality.
He's like his brother. (NOT lIe's alike his b"'ther.) Alike is not often used before a noun (see 12). Compare:
His two daughters are very much alike.
He's got two very similar-looking daughters. (NOT ••• alike titll:tghters.)
35 all (1): introduction 1 three or more items
All refers to three or more items. Compare: I'll take aU three shirts, please.
I'll take both shirts. (NOT ••• all tw6 shirts.)
alike 34
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