1. Just can indicate a short period of time when something happened.
I have just arrived.
It has just broken.
2. It can have belittled meaning too.
I am just a woman.
It is just an ordinary dog.
1. Only has a meaning of one.
I am the only woman here with degree.
This is the only restaurant over here in this village, no more choice.
2. It can be an adverb
It is only a short time till we get there.
Do not scream! It is only water i splashed on you and it is very hot now.
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