In this task, you're given the title of a story consisting of five sentences, numbered 1 through 5. Your job is to determine which two sentences need to be swapped sentences in order to make a story that makes complete sense and is befittingly titled. Indicate your answer using the numbers of the two sentences in order, such as '34' or '25'. The first digit refers to the sentence which should come first in the story.

Title: Tree House. Sentence 1: Sam went to the store yesterday and bought some wood. Sentence 2: When he finally let us see his project we were amazed. Sentence 3: He worked in his backyard all day. Sentence 4: He would not tell us what he was building. Sentence 5: Sam built the best tree house I have ever seen.
24