In this task, you need to replace a letter in the sentence with another given letter.
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Question: Sentence: 'some tracks for a rail way system near a building'. Replace the letter 'a' with 'h' in the sentence.

Answer: some trhcks for h rhil why system nehr h building

Question: Sentence: 'a couple of giraffe standing next to each other in a forest'. Replace the letter 'a' with 'w' in the sentence.

Answer: w couple of girwffe stwnding next to ewch other in w forest

Question: Sentence: 'a bus driving down the street beside a taxi cab'. Replace the letter 'u' with 'a' in the sentence.

Answer:
a bas driving down the street beside a taxi cab