I can either measure or govern but that the basic straight thing I can be

Put your cousin to sleep, When split in half and then swapped. Your face is to this, as a floor is to mops. With you while cunsuming, your lap it’s atop. Tell me, what’s your favorite? Be it paper or cloth?

I can make sure nothing leaks or swim in the ocean

I hide a smile, I guard a gasp, I dress for balls or stop a rasp. On stage I'm drama, in clinics I task. What slips on quick?

With strings in hand, I charm the ear, I sing and I weep without a tear. Hands awaken my hidden voice, and through my chords I speak with choice.