at first = in the beginning
“At first I couldn’t understand my teacher, but then the lessons became easier.”
at hand = nearby, available
“I always keep an eraser at hand just in case.”
at home = when you are in your house
“I can relax when I’m at home?”
at large = not yet captured
“Police say that the robbers are still at large.”
at (long) last = finally
“We’re on vacation at last!”
at least = to add a positive comment about a generally negative situation
“It’s not everything we wanted, but at least it’s a start.”
at once (1)= immediately
We need you to start at once.
at once (2) = at the same time
“You shouldn’t try to do everything at once!”
at risk = when there may be a negative result
“How many jobs are at risk if the pandemic continues”
at school = when someone is studying/teaching at a school
“Is your daughter at school this morning?”
at the moment / at present = now, but with a temporary meaning
“At the moment I’m staying with friends.”
at work = when you are at the place where you work
“I’m at work now.”