You've met the Subjunctive. Now, let's master its past form: the Imperfect Subjunctive. This is where you express hypothetical "what ifs."
Used after "Si" (if) to talk about things that aren't true but you wish they were.
(If I were rich...)
Take the 3rd person plural of the Preterite (ellos hablaron), drop the "-ron", and add: -ra, -ras, -ra, -ramos, -rais, -ran.
"Si tuviera tiempo, viajaría más." (If I had time, I would travel more.)
"Even if it might be..." (Uncertainty)
"So that you understand..." (Purpose)
"Without anyone knowing..."
Pick the correct hypothetical form!
You've mastered the mood. Only one more hurdle: **Por vs Para & Prepositions**.