It could take 4-6 months before the first batch（批）of vaccines （疫苗）are available to fight A/H1N1 flu ________ as swine flu, WHO officials said.
A. known B. to know C. knowing D. having known
Young people tend to get up very late unless ________ to rise early.
A. required B. requiring C. they were required D. to require
No reader ________ take away a book from the library without the permission of the librarian.
A. need B. might C. shall D. will
. --Did you see ________ may be the longest total solar eclipse （日全食）in 500 years yesterday?
--No, it was cloudy above my city at that time.
A. what B. that C. who D. all
________ a two-year period, Nancy became addicted to painkillers （止疼药）.
A. Beyond B. Above C. Since D. Over
. At noon in summer the villagers like to seek shade ________ the air is cooler.
A. in where B. in which C. where D. the place where
