What is the Subjunctive Mood?

Well, subjunctive it's just expressing ideals or imaginary situations.
Example: I wish you were here.
The use of subjunctive in the Romance languages such as Italian, French, Spanish and Portuguese is very common. People use it for wishes, requests, to express emotional states, doubtful and hypothetical situations.
- Me gustaría que estuvieras aquí (Spanish) 
- Vorrei che tu fossi qui (Italian)
- J'aimerais que vous soyez ici (French)
_ Gostaria que você estivesse aqui (Portuguese)

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