To rest significa descansar.
No significa restar, que se traduce por to subtract, to take away.
EXAMPLES:
- She spent the whole afternoon resting in her room and then went out to party. Pasó toda la tarde descansando en su habitación y luego salió de fiesta.
- He decided to stop watching TV for a few hours to rest his eyes. Decidió dejar de ver la televisión por unas horas para descansar la vista.
- He told us that he would not rest until he found out what had really happened. Nos dijo que no descansaría hasta averiguar lo que realmente había sucedido.