The preposition ACCORDING TO has several basic meanings:
1) as stated or reported by sb or sth:
According to Principal Jones, the school will be closed Friday because of the heavy snowfall.
= Principal Jones says that the school will be closed Friday because of the heavy snowfall.
According to a recent survey, over 80% of children in this country eat more than they should.
= A recent survey says that over 80% of children in this country eat more than they should.
2) as required by a plan, rules or directions:
I always tried to do everything according to the rules.
Let’s hope everything will go according to the plan.
You should do it according to the directions I gave you.
3) in a way that is based on sth:
You will be paid according to how many items you produce.
Could you please arrange these books according to their author?
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