The Grammar Guide Spelling What is the difference between 'si' and 'is'?

What is the difference between 'si' and 'is'?

What is the difference between 'si' and 'is'?

The words si and is are often confused by writers. Do you know the difference?

Is means *the third person singular present indicative form of to be * when used as a verb.

Si means a syllable used in solfège to represent the seventh note of a major scale when used as a noun.

Out of the two words, 'is' is the most common. It appears about 657 times more frequently than 'si'.



It's easy to mistype words that have the same letters in a different order.

Is is a verb. It is the third person singular present indicative form of "to be."

Si is sometimes used to denote the seventh tone of a musical scale.

Should I use 'Je ne sais si' or 'Je ne sais is'?

You should use 'Je ne sais si'. These phrases are often confused by writers.

Should it be 'ne sais pas si' or 'ne sais pas is'?

The right phrase is 'ne sais pas si'. These phrases are often confused by writers.

What's the right phrase 'si si si si' or 'is is is is'?

You should use 'si si si si'. These phrases are often confused by writers.

What's the correct phrase 'si si si si' or 'is is is is'?

The correct phrase is 'si si si si'. These phrases are often confused by writers.

Which is right 'si si si si' or 'is is is is'?

You should use 'si si si si'. These phrases are often confused by writers.

Is the phrase 'is one of the' or 'si one of the'?

The right phrase is 'is one of the'. These phrases are often confused by writers.

Should it be ', and it is' or ', and it si'?

You should use ', and it is'. These phrases are often confused by writers.

Is the correct phrase ', but it is' or ', but it si'?

The right phrase is ', but it is'. These phrases are often confused by writers.

Is the expression ', there is no' or ', there si no'?

The right phrase is ', there is no'. These phrases are often confused by writers.

What's the correct phrase ', that is ,' or ', that si ,'?

The correct expression is ', that is ,'. These phrases are often confused by writers.

Some synonyms of si are: ti, B

Some synonyms of is are: exists, inhabits, does

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The definitions in this article were adapted from Wiktionary.

Examples of si in a sentence

Then si-ic set the percolator aside and came to the door.
- Spade & Archer: the prequel to Dashiell Hammett's The maltese falcon by Joe Gores
It was said: Si fueris Romae, Romani vivito more, and quite sensibly, too.
- The Midwich Cuckoos by John Wyndham
I kept do-si-doing round the wrong way."
- Death Mask by Graham Masterton
Without more ado he sat down and plucked the si rings.
- An affair to forget by Rachel Lindsay
WINAPI DllMain(  HINSTANCE hinstDLL,  DWORD fdwReason,  LPVOID lpvReserved){    STARTUPINFO si;
- Hacking: The Next Generation by Nitesh Dhanjani;Billy Rios;Brett Hardin

Examples of is in a sentence

Old lady Metz is probably giving her an earful about us right now, though."
- The heart of Devin MacKade by Nora Roberts
And remember, dear, this is Paul’s school.
- The Battle of the Labyrinth by Rick Riordan
The plane is on its way.
- From Russia with love: a James Bond novel by Ian Fleming
Isn’t that true?”
- The wandering fire by Guy Gavriel Kay
This is a work of fiction.
- The Replacement Child by Christine Barber

Test yourself

Choose the missing word in each question.