These statements are accompanied by a series of explanatory notes.这些陈述后面有一系列解释性注释。There are explanatory notes at the back of the book.书后有注解。See explanatory notes at the foot of this page.参见本页下端的注解....
Where extraterrestrial civilizations may be rare , there is something that is rarer still: A girlfriend.虽说外星生命及其稀少, 但还是有一种生命比它更稀少: 女朋友.The results show that rarer variants are distributed more unevenly among populations....