Why Hyphens Matter

I mention compound adjectives occasionally; here’s a good example of the difference in meaning when you hyphenate or don’t hyphenate.

Sometimes you have two or more modifiers before a noun. If the first word refers to the next one, you hyphenate them and they function as one word. If they separately refer to the noun, don’t hyphenate. 

I think this lake is in Minnesota someplace

She is correct! To have “big” refer to the mosquitoes, it should be “big-mosquito lake.”

PS—yes, “mosquito” is a noun, not an adjective. But it’s being used as an adjective. We call this using the noun attributively.