How to create a Google test that allows the test taker to respond in their own words, and still get a correct answer

Does anyone know how to create a Google test that allows the test taker to respond in their own words, and still get a correct answer? I’m running into an issue where Google forms only allows you to respond exactly how the wording is placed for the correct answer, and everything else will be marked wrong. Even if it’s correct. For example, What color is the sky? If I put the correct answer in the answer key is Blue. Then the test taker could answer blue, and it would be marked wrong because B is not capitalized. I need help