Correct spelling, explanation: which is one of the basic English pronouns used to create questions or introduce relative clauses known as wh-words. If we classify which as a wh-words we need to remember about the right spelling, with wh at the beginning. This is why the spelling wich is not correct and can be either a misspelling or a simplified phonography, as the h is silent. The only correct spelling is which.

Definition of which:
pronoun: Which is used to create a question where the number of posibilities is limited.
Which dress should I wear to the party – the pink or the red one?
Which can be used to point to a particular thing that is being reffered to.
It was a problem which they should not discuss in public.
Which can be used to add an extra information and introduce a relative clause.
She promised to show me how to bake a pie, which was very nice of her.

Idioms with which:
– which is which: describes two very similar things or persons
The twins looked so alike many couldn’t tell which is which.
– which way to turn: what to do or where to search for help
In this hard times people often do not know which way to turn.

Incorrect spelling, explanation: wich is the incorrect spelling of the pronoun which. Which is one of the well-known wh-words that are used in English language to create questions and introduce relative clauses. To be a wh-word, which needs to start with wh. The wrong form wich may be a result of a misspelling or an effect of phonetics, because the h is silent in the speaking. This is why wich is not correct.

Incorrect spelling

Incorrect spelling