A2
used to refer to a time in the past
Dictionary examples:
I started a diet one hour ago. Is it working yet? (0.0)
I ate a whole pizza five minutes ago. Now I regret it! (0.0)
My socks went missing three days ago. I blame the washing machine! (0.0)
About five months ago, I got a letter from him. (21.5)
The dinosaurs died out 65 million years ago. (22.3)
He left the house over an hour ago. (31.8)
We left New York ten years ago. (56.4)