Only then did I realize that it was foolish to ___ my friends and never contact them.

_________ the people lost their lives in thetraffic accident.

It is now widely acceptable thathibernation is _____ sleep for animals

_______ does it snow so heavily in South China as it did in the winter of 2007 [ ]

Mr. Fox fell ill, thus __________ itnecessary for us to find another person for his job.