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

Example Input: Sentence: 'there is a piece of a cake on the plate and a cup of drink'. Replace the letter 'r' with 'u' in the sentence.
Example Output: theue is a piece of a cake on the plate and a cup of duink

Example Input: Sentence: 'there is a big room with furniture and items inside'. Replace the letter 'e' with 'k' in the sentence.
Example Output: thkrk is a big room with furniturk and itkms insidk

Example Input: Sentence: 'an office is shown with a desk and a window'. Replace the letter 'c' with 'h' in the sentence.
Example Output:
an offihe is shown with a desk and a window