and may confidently expect that the flag which has waved its untarnished folds over every sea will still float in undiminished honor. 并自信地期望那曾在每一海面上飘扬而不受沾污的旗帜仍将以未损的荣耀飘扬。 But these,like many other subj
全球变暖是我们目前面临的一个大问题，不过全世界都过分关注二氧化碳，却忽略了另外一个重要的气体——甲烷。 Fred Krupp: Let's launch a satellite to track a threatening greenhouse gas 我们能否发射一颗卫星来追踪威胁地球的温室气体？ We've got a big problem on our hands with global
