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previously; before; earlier; formerly; recently
first; before (something or someone else); ahead (of); earlier
beforehand; in advance; ahead of time
先に報告してから話し合いを始めた。
We started the discussion after reporting first.
先に来ておいてよかった。
It was good that I came early.
先に決めておかないと後でもめることになる。
If you don't decide ahead of time, you'll end up arguing later.