Let's fish in the river.

Spearfishing with a hand-held spear from land, shallow water is no easy task, but you are up for the challenge. You look for a calm and shallow stretch of river, as there water clarity is higher. You patiently wait for the fish to pass by, and then, when you strike, it's necessary to account for optical refraction at the water's surface, which makes fish appear higher in their line of sight than they are. By experience, you have learned to aim lower in order to actually catch the fish.

Time to make the dexterity check in order to determine whether you are sucessfull or not. Roll a six sided dice. Your dexterity modifier is +1, so just add 1 to the (six sided) dice result, and then another +1 as a bonus for having an adequate tool for fishing. If it's 4 or higher, you succeed. If it is 3 or lower, you fail.