We use 'which' to ask someone to choose or identify something from a specific group. It helps to know the options already.
Which color do you like best?
Which book is yours on the table?
'Which' introduces more details about a thing or group. It connects the extra information to the main idea.
I have a house which is very big.
She chose the dress which was red.
'Which' helps to point to one or many items when we talk about a known group. It shows choice or selection.
Which shirt do you want to buy?
Which keys did you find on the floor?
Sometimes 'which' is used to show surprise or strong feeling about a question. It emphasizes the unknown choice.
Which surprise to see you here!
Which decision did you take so quickly?
'Which' can connect a whole idea or fact mentioned before to add more information or show result. It is common in formal writing.
He missed the bus, which made him late.
She failed the test, which surprised everyone.
'Which' comes before a noun in questions to ask for a specific choice from known options. It helps find the correct answer clearly.
Which way is the station?
Which day do you want to meet?