Can you edit the timing of a recorded sequence?

Specifically, I may want to add a few seconds into a pause for a character, or I may want to reduce a pause. This could be for comic timing, or it could be wanting to slip and slide one character to fit their actions and audio with another character in the scene.

I see how how  move the timelines earlier or later, but not how to add time in the middle of a sequence.

This is necessary for getting the best timing of multiple characters. Is there a way to do it?