That is to say

Pro Tip 1/3

Use 'that is to say' to make sure the listener understands exactly what you mean.

You'll be in charge, that is to say, you're the team leader for this project.

Pro Tip 2/3

It helps prevent misunderstandings by providing clarity to a previous statement.

I enjoy solitary activities, that is to say, I like being alone.

Pro Tip 3/3

Use it to emphasize the most important part of your message.

She is a vegetarian, that is to say, she doesn't eat any meat at all.