Which is a Question That is Hard to Ignore

Do the following sentences say the same thing?

My house that has a fence all round it needs to be painted.

My house, which has a fence all round it, needs to be painted.

There is a difference between the two statements, however subtle. The first sentence specifies that only the house that has a fence all round it needs to be painted. I may have other houses that belong to me: I am saying nothing about them. I am specifying that only the house that has an enclosing fence should be painted. The phrase ‘that has a fence all round it’ is restrictive and is essential to the sentence.

The second sentence prefaces the ‘which’ with a comma; like a parenthesis, it provides supplemental information about ‘my house’. This nonrestrictive or non-defining clause could be deleted without altering the meaning of the sentence.

That, who, whom, whose, which, where, when, and why are called relative pronouns. They are used to introduce subordinate clauses that give information about the main clause.

The relative pronoun ‘that’ can be used only in defining/restrictive clauses. It can also be substituted for ‘who’ (referring to persons) or ‘which’ (referring to things).

Mahatma Gandhi was a great leader who lived in the early 20th century.

More examples of restrictive phrases:

The book that I borrowed from you is excellent.

This is the house that I built with great pride.

Parents who are not strict with their children only harm them.

The candidate who spent extravagantly lost the election.

It took me a while to get used to the new neighbors who had a dog that barked at all the passers-by.

When you use ‘which’ in a restrictive clause (without using commas), your computer may register its protest through wavy underlines, but using ‘which’ this way is not incorrect. Again, the sentence with ‘which’ is more formal than the one with ‘that’.

The hotel that makes the best biryani in town has been closed recently. – less formal

The hotel which makes the best biryani in town has been closed recently – more formal

Examples of non-restrictive elements (set off by commas, could be deleted):

My niece, wearing a yellow frock, is playing in the living room.

Mangoes, which are my favorite fruit, are available in plenty in summer.

My daughter, grinning from ear to ear, announced she is pregnant.

It is up to you, Monica Sappleton, to girdle up for the challenge.

She was, however, too determined to give up.