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'on vs upon' and 'in vs into'

They are very similiar and I think there could be an equation, literllay: upon= up+on and in+to.

Is ther any big difference when learners of English should keep in mind?

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In most uses, on and upon are interchangeable: except in some set expressions, on is more common. There are some transferred meanings of on where you can't use upon (for example, on television, on Thursday) but others where you can (eg as a temporal conjunction on seeing him = upon seeing him).

Into always has a meaning of movement or transition. In can have this meaning (eg I put it in/into the car), but is also used for static position (It was in the car) and in this sense, it cannot be replaced by into.

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