How to Use the Spanish Conditional Tense to Express Probability or Conjecture
In this article you will learn how to use the Spanish conditional tense (mood) to express probability or conjecture. I recommend that you pay close attention because in the English language the conditional tense (mood) is not used in the same manner. Here are some cases:
1. When there is doubt, conjecture, or probability about the future from the perspective of the past, the conditional tense is used. Normally in English you use “would” and a verb, e.g. Sabía que vendrían a tiempo (I knew they would arrive on time).
2. You can also use it to express conjecture or an assumption about the past. In English you would use must have and a verb e.g. En 1918 mi abuelo viajaría a Guadalajara cada semana (In 1918 my grandpa must have traveled to Guadalajara every week). In English you may also express the same idea in different ways, i.e. using could ¿en dónde estaría el gato? (Where could the cat be?)
3. Another use is when you speculate about events or actions that may or may not happen (this is why some call the conditional the hypothetical future), e.g. sería maravilloso viajar a la luna (it would be wonderful to travel to the moon).
Don’t confuse the conditional tense with the future tense when expressing probability or conjecture. The difference is that the future tense is used to express present probability while the conditional tense expresses past probability.
Present probability – Past probability
Serán las cuatro de la mañana – Serían las cuatro de la mañana
It must be four in the morning – It must have been four in the morning
Me pregunto ¿quién será? Me pregunto ¿quién sería?
I wonder who he/she is? I wonder who he/she was?
Tendrá unos 15 años de edad – Tendría unos 15 años de edad
He/she is probably about 15 years old – He/she was probably about 15 years old
Now that you know how to use the conditional tense in Spanish in order to express probability or conjecture, I recommend that you practice making up some sentences using the conditional tense to create more examples. The more that you use this tense to express probability or conjecture, the more natural it will feel. As I mentioned earlier, in English this tense is not used this way and for that reason it may feel somewhat strange to you at first.
Besides creating your own example sentences, I recommend that you use the Learning Spanish Like Crazy course to speak conversational Spanish. It is available at online book stores. I also recommend that you find a native Spanish-speaking friend who you can practice your Spanish with.