How to use “non so se” in Italian

Non sapere se Italian
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How to use “non so se” in Italian

If you’re here, it’s probably because you’re wondering what verb to use after “non so se”, which means “I don’t know if”.

And you’re obviously asking yourself how to use “non so se” in Italian.

Well, that is a very good question.

Do you want to know why?

It’s because even if some Italian native speakers would go for one verbal mood or the other (either the subjunctive or indicative), they wouldn’t be able to explain why.

And to be honest, there’s no right or wrong answer.

It depends on what you want to say and how formal you want to sound.

Let’s read more about this controversial topic!

How to use non so se

Sapere: conjugation

Before we go into more detail, let’s see (or review) the conjugation of the verb sapere.

Sapere is an irregular verb in the present indicative, which means it doesn’t follow a pattern.

Here’s its conjugation:

io so
tu sai
lui/lei sa
noi sappiamo
voi sapete
loro sanno

So, if you’re talking about yourself you can say “non so se”. But if you’re talking about someone else, you can say “non sai se” (you don’t know if).

How to use non so se in Italian

Non sapere se: indicative or subjunctive?

We already mentioned in other posts about the subjunctive that we use the subjunctive to express doubt, uncertainty, and hypothetical situations.

This is why, in theory, since non sapere (not to know) explicitly expresses uncertainty, we should use the subjunctive after it.

However, in spoken Italian, it is very common to find the indicative. It just sounds more natural and less formal.

So, your choice will depend on how formal you want to sound.

If you use the indicative, you’ll sound more natural and spontaneous.

If you use the subjunctive, you’ll sound more intellectual and unnatural.

This expression is not as strict as other expressions that do need the subjunctive and wouldn’t accept the indicative.

For instance, purché (provided that) and affinché (in order for X to) trigger the subjunctive BUT they are very formal words that you would find in written texts.

Non so se indicative or subjunctive

Non sapere se + indicative

Let’s focus on non sapere se followed by the indicative tense.

The indicative is just the “normal” and most common verbal mood in Italian, as opposed to the subjunctive, which is less common.

As we already mentioned, most of the time, the indicative sounds more natural.

And, since sometimes native speakers tend to go for what sounds more spontaneous, you’ll hear non so se followed by the indicative very often.

The indicative has different tenses: past, present, and future.

Let’s have a look at some examples with these three tenses:

Non so se sono andati al cinema.

I don’t know if they went to the cinema.

Non sappiamo se vengono.

We don’t know if they’re coming.

Non so se funzionerà.

I don’t know if it’ll work.

Non so se subjunctive or indicative

Non sapere se + subjunctive

As we said, the subjunctive can sometimes sound very formal and unnatural.

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However, interestingly, sometimes it sounds better.

If you’re not sure, you can always ask a native speaker or just go for it.

In any case, you won’t be wrong.

Like with the indicative, we can use all types of subjunctives:

Non so se sia possibile.

I don’t know if it’s possible.

Non so se parlasse sul serio.

I don’t know if she was speaking seriously.

Non sappiamo se Antonio abbia avuto il coraggio di parlare.

We don’t know if Antonio had the guts to talk.

Non so se followed by congiuntivo o indicativo in Italian

Non sapere se + infinitive

We can also use the infinitive after non sapere se.

The infinitive is the base form of a verb, those words ending in -are, -ere, and -ire (like mangiare – to eat, cadere – to fall, dormire – to sleep).

We can only use the infinitive if the subject of the sentence is the same in both clauses, as you can see in the sentence below:

Non so se venire stasera.

I don’t know whether to come tonight.

In the example, the person who doesn’t know is the same as the person who will or won’t go somewhere tonight.

Here’s another example:

Non sappiamo se mangiare a casa o mangiare fuori.

We don’t know whether to eat in or out.

Here, the people who don’t know are the same as the people who will or won’t eat in or out.

It’s pretty much the same in English. If you’re not convinced, have a look at the translations again.

Non sapere se in Italian

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