Learn Spanish (Latin America): Me gustaría que pusieras la estampilla en el álbum. - I would like you to put the stamp in the album.

When expressing a polite request or wish using the conditional tense in the main clause (like Me gustaría), Spanish requires the imperfect subjunctive in the subordinate clause (que pusieras). Even though you are talking about a current or future desire, the conditional 'pulls' the subjunctive back into its past form to soften the request.

I always want to translate 'you to put' as an infinitive. Why do we use que + a conjugated verb here?

In English, we use an infinitive for this structure ('I would like you to put'). In Spanish, when the subject changes from the person wishing (I) to the person doing the action (you), you cannot use an infinitive. You must use que followed by a conjugated subjunctive verb. If you were doing both actions ('I would like to put'), you would use the infinitive: Me gustaría poner.

Could I use the present subjunctive (que pongas) instead of pusieras?

Grammatically, no. The strict sequence of tenses rule dictates that a conditional trigger like Me gustaría requires a past subjunctive like pusieras. You might occasionally hear native speakers use the present subjunctive in very casual speech, but for correct grammar, always stick to the imperfect subjunctive here.

Is pusieses also correct instead of pusieras?