orbit

地球围绕太阳的运行轨道是椭圆形的。

The Earth's ___orbit around the Sun is elliptical in shape.

火星有两颗小卫星围绕着它运行。

Mars has two small moons that ___orbit it.

卫星在近地轨道上，每90分钟绕地球一圈。

The satellite is in a low Earth ___orbit, circling the planet every 90 minutes.