TASK DEFINITION: Given a sentence, generate a new sentence by performing small changes on the sentence. Here, make sure that the changes are semantically related and syntactically similar to the input. And the generated sentence should have high commonsense plausibility, that is to have reasonable probability of it being true.
PROBLEM: People with money can box for items for sale .

SOLUTION: People with money can ay for items for sale .

PROBLEM: You are likely to investigate a monkey in the zoo and some homes .

SOLUTION: You are likely to call a monkey in the ground and some homes .

PROBLEM: You can build swim castles on the beach .

SOLUTION:
You can sketch sand castles on the drawing .