MEANING-Single action  brings two benifits , Double work accomplished with one step, to solve two problems with a single solution.

Explanation -Sometimes people  get two things done with a single action.

1 -Sunny kills two birds with one stone by gifting his child educational books.

2-She chose a marketing job as she loves to travel, killing two birds with one stone .

3 -people invest in several financial plans to save the taxes;killing two birds with one stone.