Prices fluctuate, in response to harvests, natural disasters and political instability; and when they rise, it takes some time before new sources of supply become available.
价格会随着收成、自然灾害和政治不稳定而波动;当价格上涨时,需要一段时间才能找到新的供应来源。
2
Coal and natural gas are mainly used for electricity generation, whereas oil is used mostly to power transportation, yet the prices of all these energy sources are linked.
煤炭和天然气主要用于发电,而石油主要用于给运输提供能量,但所有这些能源的价格是相互关联的。
3
The main reason is that London is home to eight mining and commodity companies at a time when natural resources prices have been soaring.