Biofuels are based on biological sources, like grains and oil seeds, forestry residue, used cooking oil, even municipal solid waste.

生物燃料使用生物原料制造，例如谷物和油菜籽、林业剩余物、地沟油甚至是城市固体废弃物。

Every Spring, when oil seed rape flowers are in full bloom, as people meander between these fields in small boats.

每个春天，当油菜花盛开时，人们乘坐着小舟在这些垛田间蜿蜒而行。