Language is fluid, and usage changes. A case in point is the subjunctive (il congiuntivo), which in English is rapidly becoming extinct. Phrases like "I suggest you go home immediately" and "Robert wishes that you open the window" are not in frequent use anymore.
In Italian, though, the subjunctive tense is alive and flourishing, both in speaking and writing. Rather than stating facts, it expresses doubt, possibility, uncertainty, or personal feelings. It can also express emotion, desire, or suggestions. The table below provides examples of three regular verbs conjugated in the present subjunctive tense.
Typical phrases that call for the subjunctive tense include:
Credo che... (I believe that...)
Suppongo che... (I suppose that...)
Immagino che... (I imagine that...)