When should I use the subjunctive mood?

Unlike a tense such as past or present, the subjunctive mood refers to the attitude of the speaker. The subjunctive is commonly used to express doubt, desire, wishes, requests and more. A good way to remember when to use the subjunctive is through the acronym W.E.I.R.D.O - Wishes, Emotions, Impersonal expressions (for example, "es interesante que...es posible que), Recommendations or requests, Doubt and Ojala, which means "I hope." This also applies to the synonym "Espero que."Generally, a subjunctive sentence will have three indicators that show the subjunctive needs to be used. If it has two subjects, a relative pronoun such as "que" or "quien", and one of the WEIRDO criteria, then it is subjunctive. Subjunctive is formed by taking the first person singular conjugation of a verb in the present tense, removing the ending and replacing it with the opposite conjugation, so verbs that end in -ir/-er take on -ar endings and vice versa, e.g. "tienes" would become "tengas" and "lees" becomes "leas." There are also some irregulars to watch out for.Here are a few example sentences:Espero que apruebes tus examenes. - Contains a wish or hope, two subjects and a relative pronoun.Es probable que ella gane la carrera. - Contains an impersonal expression, and, again, two subjects and a relative pronoun.