Uses of si and sí in Spanish – The Spanish Si clause

The word “si” is a conjunction whose use is to express condition, supposition and also to introduce interrogative sentences in the indirect style. “Sí” with an accent, is an adverb that expresses affirmation or it is also used as a pronoun and always carries an accent (tilde). 

In addition to these uses, these two words are used in other contexts. In this post we are going to see when to use si and when to use sí with example sentences. Let’s start… 

When do we use si (without an accent – tilde)?

Si is a conjunction that is used: 

• to express condition. In conditional sentences it can be placed at the beginning or in the second part of the sentence. 

Examples:

Spanish	English
Si tenemos tiempo mañana, vamos a pasar por el centro comercial.	If we have time tomorrow, we are going to stop by the mall.
No podremos viajar si no tenemos los pasaportes al día.	We won’t be able to travel if we don’t have our passports up to date.

• to express supposition. 

Example: 

Spanish	English
Si llegaras temprano el lunes, podríamos empezar la reunión antes.	If you arrived early on Monday, we could start the meeting earlier.

• to denote affirmation/confirmation. 

Examples: 

Spanish	English
No entiendo por qué no trajiste los documentos si te lo pedí veinte veces.	I don’t understand why you didn’t bring the documents if I asked you twenty times.
¿Por qué te enojas si tú me  dijiste que no era necesario que venga?	Why are you getting angry if you told me it was not necessary for me to come?

• after the words “como” or “que” to compare. 

Spanish	English
Habla como si supiera todo.	She/He talks as if he knows everything.
Estaba más feliz que si hubiera ganado la lotería.	I was happier than if I had won the lottery.

• in the indirect style for questions. 

Spanish	English
Me preguntó si había terminado de trabajar.	He asked me if I had finished work.
La camarera nos preguntó si queríamos más café.	The waitress asked us if we wanted more coffee.

When do we use sí?

• As we saw earlier sí is an adverb denoting affirmation and generally most often used to answer total questions. 

Examples: 

Spanish	English
– ¿Hablaste con tu padre ayer?- Sí, lo llamé después del trabajo.	– Did you talk to your father yesterday?– Yes, I called him after work.
– ¿Quieres que te llame un taxi?- Sí, muchas gracias.	– Do you want me to call you a cab?– Yes, thank you very much.

• As an adverb it also contrasts two elements in a sentence. 

Examples: 

Spanish	English
Yo no ví lo que pasó, pero ella sí.	I didn’t see what happened, but she did.
Ellos no quieren nada para beber, yo sí.	They don’t want anything to drink, I do.

• It is also used as a masculine noun to express approval or permission. 

Examples: 

Spanish	English
Mis padres me dieron el sí para comprarme el coche.	My parents gave me the yes to buy the car.
Ya tenemos el sí de los inversores, ahora tenemos que hablar con el banco.	We already got the yes from the investors, now we have to talk to the bank.

Phrases with sí for consent

• dar a alguien el sí: to grant

Example:

Spanish	English
¡Nos dieron el sí!	They gave us the yes!

• no responder ni un sí ni un no: not giving a concrete answer.

Spanish	English
– ¿Qué te dijeron de los planos? ¿Están aprobados?- No respondieron ni un sí ni un no, no podemos avanzar hasta que estemos seguros.	– What did they tell you about the plans? Are they approved?– They did not answer yes or no, we cannot move forward until we are sure.

• por sí o por no: to express cause or reason for a decision made. 

Spanish	English
– ¿Qué van a hacer al final?- Vamos a preguntarle al gerente, por sí o por no, tiene que saber los cambios que queremos.	– What are you going to do in the end?– We are going to ask the manager, yes or no, he has to know the changes we want.

• porque sí: without cause or justified reason. 

Spanish	English
Nuestro profesor cambió los temas del examen porque sí, fue una sorpresa para todos.	Our teacher changed the exam topics just because, it was a surprise for everyone.

• sí que: adverbial locution to contrast. 

Spanish	English
Ella sí que sabe lo que hace.	She really knows what she is doing.

• Sí is also the reflexive form of the pronouns él, ella and usted and goes after a preposition or followed by the words “mismo” and “solo“.

Examples: 

Spanish	English
Él siempre piensa en sí mismo.	He always thinks of himself.
¿Puede hacerlo por sí solo o necesita ayuda?	Can he do it by himself or does he need help?
Ella es muy segura de sí misma.	She is very self-confident.

Phrases with sí with an accent (tilde) 

• de por sí: means separately or apart. 

Spanish	English
De por sí, ya no tengo síntomas.	Of itself, I no longer have symptoms.

• de sí: naturally, without help. 

Spanish	English
Lo hizo de sí.	He did it by himself.

• para sí: to think or say something mentally, for oneself. 

Spanish	English
Lo dijo para sí, no era para nosotros.	He said it for himself, it was not for us.

• ¿Sí?: to answer a call. 

Spanish	English
– ¿Sí? Diga – Habla Josefina, ¿está Ana?	– Yes? Hello– Josefina speaking, is Ana there?

• to express surprise. 

Spanish	English
– Jugué al número que soñé anoche y gané. – ¿Sí? ¡Vaya, qué suerte!	– I played the number I dreamed of last night and I won. – Yes? Wow, what luck!