Well, it also illustrates that one of the things you do after you introduce a vaccine, you can't stop there, you have to continually watch what's happening with this disease in your population.

同时,也告诉我们,将疫苗推向公众后,你不能就此放手,你必须得继续观察,接种过疫苗的人中,该疾病的发病情况

耶鲁公开课 - 生物医学工程探索课程节选

Every Tuesday and Wednesday, much of Europe's male population tunes in to watch the Champions League, the pan-European football championship embracing the best teams from all over Europe.

ECONOMIST: Charlemagne

Record numbers of about seven million people - or one in seven of the population - are expected to watch the match on large open-air screens in the biggest street party the country has ever seen.

BBC: South Korea reaches fever pitch

Dr Welch can now track where an individual salmon spends its life and watch trends in an entire population.

ECONOMIST: Oceanography