A vs An

If a noun starts with a vowel, I should use the article, _, before it. a an If a noun starts with a consonant, I should use the article, _, before it. a an a banana computer gorilla monkey child chair hamburger pillow bed school watermelon an orange igloo apple octopus eel eye ear orangutan ostrich adult onion I took _ test that was very difficult. a an We got to pet _ stingray when we went to the zoo. a an We were invited to _ extravagant party this summer. a an