Spanish Phrase
No estoy muy seguro de esto.
Meaning
Literally, “I am not very sure about this.” The speaker expresses a moderate level of doubt, indicating that they have some knowledge but lack full confidence.
When to use
Use this sentence when you want to convey mild uncertainty about a fact, a decision, or a piece of information. It works in both informal conversations and more formal settings such as meetings or classroom discussions.
✦Grammar Breakdown
Noestoymuysegurodeesto
Negación (No)
The word 'No' is placed before the verb to negate the statement.
Verbo estar (estoy)
Estar is used for temporary states or conditions; 'estoy' is the first‑person singular present.
Adverbio de intensidad (muy)
Muy intensifies the adjective that follows; it does not change form.
Adjetivo (seguro)
Seguro means ‘sure’; it must agree in gender and number with the subject (seguro/segura).
Preposición (de)
De introduces the complement that explains what the speaker is (or isn’t) sure about.
Pronombre demostrativo neutro (esto)
Esto refers to an idea, statement or situation previously mentioned; it is gender‑neutral.
🗨In Conversation
No estoy muy seguro de esto.
I'm not very sure about this.
¿Qué parte te parece confusa?
Which part seems confusing to you?
✕Common Mistakes
No es muy seguro de esto.
Using 'ser' instead of 'estar' makes the sentence sound like a permanent characteristic, which is not the intended meaning.
No estoy muy segura de esto.
If the speaker is male, 'segura' is a gender mismatch; the adjective must agree with the subject.
No estoy muy seguro de este.
‘Este’ is a masculine demonstrative adjective that needs a noun; the neuter pronoun ‘esto’ is required here.
↔Alternatives
No tengo mucha certeza sobre esto.
I don't have much certainty about this.
No estoy del todo seguro de esto.
I'm not completely sure about this.
Tengo dudas sobre esto.
I have doubts about this.
Cultural Tip
In Spanish, temporary states of confidence use estar (estar seguro), while permanent traits use ser. Saying 'No soy muy seguro' would be incorrect because 'ser' does not describe a fleeting feeling. Also, remember that the adjective must match the speaker’s gender: a woman would say 'No estoy muy segura de esto.'