且由于在另一个星系中的单颗“造父变星”的亮度就足于使其被观测到，所以它们是测算类似星系距离的首选工具。
And, since individual Cepheids are bright enough to be seen in other galaxies, they were the first tool used to estimate the distances to such galaxies.
他们在享受修甲，做脸，足疗和按摩，却由美国人民为他们埋单。
They were getting their manicures, their facials, pedicures, massages while the American people were footing the bill.
单根足尺寸的雪茄中含有的尼古丁相当于好几根根香烟中尼古丁的含量。
A single full-size cigar can contain as much nicotine as do several cigarettes.
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