TASK DEFINITION: In this task, you need to replace a letter in the sentence with another given letter.
PROBLEM: Sentence: 'a crowd watches as giraffes graze the tree tops at the zoo'. Replace the letter 't' with 'q' in the sentence.

SOLUTION: a crowd waqches as giraffes graze qhe qree qops aq qhe zoo

PROBLEM: Sentence: 'a well dressed man standing near his early bicycle'. Replace the letter 'e' with 'd' in the sentence.

SOLUTION: a wdll drdssdd man standing ndar his darly bicycld

PROBLEM: Sentence: 'a bathroom with a pedestal fan in ti'. Replace the letter 'o' with 'v' in the sentence.

SOLUTION:
a bathrvvm with a pedestal fan in ti