But because hard laughter is difficult to sustain, a good laugh is unlikely to have measurable benefits the way, say, walking or jogging does.
翻译：但是因为大笑很难持续，所以不太可能像散步或者慢跑那样有显著的益处。
Enhanced security measures since then, combined with a rise in airline travel due to the improving economy and low oil prices, have resulted in long waits at major airports such as Chicago's O'Hare International.
主干是Enhanced security measures have resulted in long waits at major airports
翻译：伴随着由于经济增长和低油价而增多的飞机出行，从那之后业已加强的案件措施导致了各个主要机场较长的等待时间，例如芝加哥的OH国际机场。