Before

Before

####Earlier than something or someone OPP after

e.g. The new road should be completed before the end of the year.

e.g. Let’s meet at our house before the show.

Five minutes/two hours etc before something

e.g. Hugh arrived just five minutes before the ceremony.

####Ahead of someone or something else in a list or order OPP after

e.g. You were before me in the queue.

####Used to say that something happens where it can be watched by people 

e.g. Italy will face Brazil this afternoon before a crowd of 100,000 spectators.

e.g. He is the actor who has performed before the Queen a number of times.

####Used to say that someone or something comes to be judged or considered by a person or group of people

e.g. The proposal was put before the planning committee.

####Used to say that one thing or person is considered more important than another

e.g. I put my wife and kids before anyone else.

e.g. In the air transport business, safety must always come before profit.

####In front of something or someone

e.g. The priest stood before the altar.

e.g. The sea stretched out before them.

####If one place is before another place on a road or journey, the first place is nearer to you than the second, so you will reach it first OPP after

e.g. The pub is 100 metres before the church on the right.

e.g. The last station before the Simplon Tunnel is my favourite.

####If there is a job or situation before you, you will have to do the job or face the situation SYN ahead of

e.g. The task of emptying the house lay before us.

####If a period of time is before you, it is about to start and you can do what you want during it SYN in front of

e.g. We had a glorious summer afternoon before us to do as we pleased.

e.g. You have your whole life before you.

Sources:

Cambridge dictionary

Longman dictionary

Oxford dictionary