水手用六分仪测量星星与地平线的角度来确定船只的位置。

The sailor used a ___sextant to measure the angle between the star and the horizon for navigation.

航海仪器将一个圆周分为六个六分仪，每个测量60度。

The navigational instrument divides a full circle into six ___sextants, each measuring 60 degrees.