How does a liquid-filled thermometer measure temperature accurately?

A liquid-filled thermometer measures temperature accurately by using the principle that liquids expand or contract with changes in temperature. As the temperature increases, the liquid inside the thermometer expands and rises up the tube, providing a visual indication of the temperature. Conversely, as the temperature decreases, the liquid contracts and moves down the tube. The markings on the thermometer scale correspond to specific temperature values, allowing for accurate measurement.