Breakdown of No estoy seguro de la respuesta.
no
no, not
la respuesta
the answer
estar seguro de
to be sure of
Questions & Answers about No estoy seguro de la respuesta.
Why do we use de after seguro?
This is an example of a governed preposition. In Spanish, the adjective seguro (when meaning "sure" or "certain") always pairs with the preposition de to introduce what you are sure about. You have to learn the phrase estar seguro de (to be sure of/about) as a fixed unit, rather than trying to directly translate English prepositions like "about."
Why is it estoy seguro and not soy seguro?
The verb you choose changes the meaning of the adjective! Estar seguro describes a state of mind, meaning "to be sure" or "to be certain." If you use ser seguro, it means something is "safe" or "reliable" (like a neighborhood or an investment). Since the speaker is expressing their own lack of certainty, we use estar.
If a female speaker is saying this, does the sentence change?
If I want to say "I am not sure THAT it is the answer", do I keep the de?
Yes! When you add que (that) to introduce a new clause, you must keep the governed preposition. The phrase becomes estar seguro de que. Leaving out the de is a common mistake for English speakers. You would say: No estoy seguro de que sea la respuesta.
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