The move is a sign of appetite for physical commodities at a time when prices have started rising again after falls last year. 此举标志着，随着大宗商品价格自去年下跌后回升，投资者对于实物大宗商品再次产生了兴趣。
And secure domestic sources of energy are particularly prized at a time when prices are volatile and many of the big oil and gas exporters are becoming worryingly nationalistic. 而且，当世界能源价格剧烈波动，当许多大型的石油和天然气的出口国由于担忧而变得民族主义，保护国内能源已变得尤为重要。
Is there a time when the conference room is free? 会议室有空著的时候吗?
I will come at a time when you are at home . 你在家的时候我会来。