Demonstrate correct use of articles and prepositions:I bought _ umbrella to go out in the rain.

Explanation

The indefinite article "an" is used before singular countable nouns that begin with a vowel sound. "An umbrella": This indicates any umbrella, not a specific one.Therefore, "an" is appropriate here because "umbrella" starts with a vowel sound ("u"), and the speaker is referring to any umbrella in general that they purchased for going out in the rain.