Asking about Certainty/Possibility

Question

Suppose I have a dictionary but I can't find it at this moment. I ask myself a question. Which of the following is the most suitable form and how is it different from the other forms?

1. Where can it be?
2. Where could it be?
3. Where will it be?

Answer 1

Which is the most suitable form? Depends on the context, but you probably want to use #2.

The difference is tense. Can and could both are asking about the possibilities of an item's location, with can having a sense of immediacy as it is present tense. Will on the other hand is future tense, and the question "Where will it be?" doesn't necessary care about where an item is right now, it cares about its future location. Take the following examples:

• Where could the serving dish be? Do you think I left it in the garage?
• Where can/could my keys be? I just set them down a moment ago!
• Where will the float be? I need to make sure that I don't park my car there or it will end up crushed!