That hose you have is part of your EVAP (fuel vapor recovery) system. If you take a look at the attached diagram, the part that says "from canister" is from your tank charcoal canister. A hose runs under the body and up into the engine compartment, connecting to your surge tank (which is the part with the black cylindrical body and blue top hose connection). One part of the hose connects to your EVAP service port, which you should be able to see on your engine.
This part didn't just fall off. It was previously removed and not installed. If you did not do service work on your engine, but recently had service work done, you should take this EVAP hose setup back to your mechanic and insist he/she properly reinstalls that hose. You are risking an engine fire by having fuel vapor getting into your engine bay when your engine is running and hot - so be extremely careful and understand your risks when driving it.
Also attached is an EVAP diagram for your model. Item 23826 (P/N 23826-22130) is the surge tank you have in the diagram, and you can see the short elbow hose and the longer one each end of the surge tank. This might give you an idea of where to find the connection points for this hose. But I would really suggest you take it back to the person who did some engine work on your car recently and have that person correct their mistake.