---____ was it _____they discovered the entrance to the underground palace?--- Totally by chance.
The island is ______ attractive in spring and autumn because of the pleasant weather in both seasons.
From that night Beijing ______ the first snowfall process since this winter, but with small amount.
One minute she burst into _____, and the next she burst out _____. We just couldn’t catch her mood (心情) at any moment.
The weather _____ fine for several days, that is, the fine weather _____ several days.
Both their grandparents ________ them ________ their excellent results.