In Spanish, the conditional tense isn't just for talking about what "would" happen. Just like the future tense can express probability in the present, the conditional tense can be used to make a guess, a hypothesis, or express probability about the past.
Wondering out loud (Questions)
When you ask a question using the conditional tense, you are wondering about a past situation. In English, this usually translates to "I wonder if..." or "I wonder what..." regarding a past event.
| I wonder how old the volcano was. | ¿Qué edad tendría el volcán? |
| I wonder why there was an earthquake yesterday. | ¿Por qué habría un terremoto ayer? |
Making a guess (Statements)
When you make a statement using the conditional tense, you are expressing that something was likely true in the past. It often translates to "It was probably..." or "It must have been...".
| The volcano was probably very dangerous. | El volcán sería muy peligroso. |
| The geologist must have been in the cave. | El geólogo estaría en la cueva. |
Guessing what happened
You can apply this same concept to any verb to hypothesize about what a person, animal, or force of nature probably did.
| The earthquake probably destroyed the village. | El terremoto destruiría el pueblo. |
| The dinosaur probably died in the forest. | El dinosaurio moriría en el bosque. |