Biting flies and the quest for new pasture drives the migration ever onwards. 会叮咬它们的苍蝇以及为了寻找新草场, 驱使它们不停的向前迁徙

105. they can cover nearly 2,000 miles during the summer months.
     差不多整个夏季能够行进2000英里
106. The wolves will starve if they don't find the caribou.
     狼若找不到驯鹿 就会饿死
107. But it's no easy task to locate prey that never stops travelling.
     但若想找到这些 脚步永不停止的猎物又谈何容易？
108. Biting flies and the quest for new pasture drives the migration ever onwards.
     会叮咬它们的苍蝇以及为了寻找新草场, 驱使它们不停的向前迁徙
109. A wolf has finally picked up the trail.
     一头狼终于找到了猎物的痕迹
110. The caribou are close.
     驯鹿近在眼前
111. At last, a chance.
     机会终于来了！

来自《行星地球 第一季 第七集 Planet Earth S01E07 伟大草原》第 108 行