Hard coal

硬煤───Hard coal

hard to imagine a planet blacker than coal, but that's what astronomers say they've discovered in our home galaxy with NASA's Kepler space telescope.───很难想象一个行星比煤炭还要黑，但是宇航员们的确声称，他们通过NASA的开普勒太空望远镜在我们所处的银河系发现了这样一颗行星。

Planning aside, nuclear plants can be hard to finance, since they cost more and take longer to build than coal - or gas-fired units.───撇开规划不说，相比用煤或煤气作燃料，核电站成本更高，建设周期更长，因而资金筹措也相当困难。

The miserable Toad, crouching in the coal-dust, tried hard to think of something to do, with dismal want of success.───可怜的托德蜷缩在煤尘里，拼命想主意，可是苦于想不出来。