Question/Answer-Keywords to sentence formulation?

Is there any repository which can generate a answer sentence given a question and the answer keyword?

For example:

  • Question: How many people are nearby?

  • Answer Keyword: 5

  • Generated Answer: There are 5 people nearby.

  • For Question/Keyword Answer generation, I am using TAPAS.

  • But I have no idea how to go from keywords to sentences.

Very grateful for any hints.