An eclipse happens when the earth and moon are in line with the sun.
地球和月亮与太阳处在一条直线上,日食就发生了。
《牛津词典》
2
During an eclipse, the sun, Earth and moonline up, leaving a darkened moon visible to observers on the night side of the planet.
月全市发生时,太阳,地球和月球连成一线,地球夜晚一侧的观察者可以看到一个变暗了的月亮。
3
The last total lunar eclipse - when the sun, Earth and Moon are almost exactly in line, with the Moon and sun on opposite sides of the planet - was in February 2008.