Breakdown of Necesitamos un anuncio que explique el proyecto.
un
a, an (masculine)
necesitar
to need
el proyecto
the project
explicar
to explain
Questions & Answers about Necesitamos un anuncio que explique el proyecto.
Why is explique in the subjunctive here instead of the normal present tense explica?
Because we are looking for an ad (un anuncio) that fits our needs, but we don't know if it actually exists yet. When we use que (that) to describe an antecedent (the noun being described) that is unknown, indefinite, or non-existent, the verb that follows must be in the subjunctive.
If we already had a specific ad in mind, would we still use explique?
No. If you were talking about a specific, known ad, you would use the indicative mood. For example, if you said, "We have the ad that explains the project," it would be Tenemos el anuncio que explica el proyecto. The subjunctive is only triggered here because we are stating a requirement for something we haven't found or created yet.
Why is explique spelled with a qu instead of a c like its infinitive form, explicar?
This is a spelling change to keep the pronunciation consistent. In Spanish, a c followed by an e makes an "s" sound. To keep the hard "k" sound from explicar, the c must change to qu when we form the present subjunctive.
Could anuncio mean anything else besides "ad"?