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: You are likely to find a steel pen in a writer's pocket.

SOLUTION: You are likely to find a steel pen in a bartender 's pocket .

PROBLEM: If you want to go to market then you should get in car.

SOLUTION: If you want to plan to market then you should get in fact .

PROBLEM: Learning how to paddle a bike would make you want to purchase a bicycle .

SOLUTION:
Learning how to ride a bike would make you want to ride a bicycle.