1. (place). He is at home; at Singapore; etc.
2. (time). He came on Monday at 3 o’clock in the afternoon.
3. (Verb of motion). We arrived at the station. (So also: to stop at; throw at; astonished at; rejoice at)
4. These are sold (or bought) at ten dollars each.
5. He came at once. (So too: at last; at ease; at leisure; to be at loss; at work; at play)
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