You already know that the modal verb zullen is used to talk about the future ("will"). However, Dutch speakers frequently use zullen to make guesses, assumptions, or express probabilities about the present.
Assumptions with wel
To say that something is "probably" true, zullen is often paired with the particle wel. Because zullen acts as a modal verb, it takes the second position in the sentence, while the main verb is pushed to the very end.
| The bus is probably on the way now. | De bus zal nu wel onderweg zijn. |
| The lock of the door is probably broken. | Het slot van de deur zal wel kapot zijn. |
Wondering out loud
When you use zullen in a question about the present, it softens the tone. Instead of a direct question, it sounds more like you are wondering out loud or asking for a guess. In English, this often translates to "could" or "might".
| What could he be busy with now? | Waarmee zal hij nu bezig zijn? |
| Where could the burglar be? | Waar zal de inbreker zijn? |
Making stronger guesses
To express different levels of certainty, you can swap out wel for other adverbs like vermoedelijk (presumably) or vast (surely).
| That is presumably the burglar. | Dat zal vermoedelijk de inbreker zijn. |
| He will surely leave something weird behind. | Hij zal vast iets raars achterlaten. |