In this task, you need to replace a letter in the sentence with another given letter.

Sentence: 'a gray elephant standing next to green bushes'. Replace the letter 'e' with 'o' in the sentence.
a gray olophant standing noxt to groon bushos

Sentence: 'this is a tennis player getting ready to serve the ball'. Replace the letter 'h' with 'y' in the sentence.
tyis is a tennis player getting ready to serve tye ball

Sentence: 'three zebras standing in the grass near each other'. Replace the letter 'e' with 'u' in the sentence.
thruu zubras standing in thu grass nuar uach othur