Theaddressbook________theemailaddressesofyourfriendsorgroupsofcolleagues.
A、makesiteasytorecallIdon'tknowhowwecanmake________onthetimetableforanymorecourses.
It________asashocktorealizethatIwasnotaloneintheroom.
Theproblem________whenthestudentsrefusedtodotheirhomework.
Whenhesuddenly________upthesubjectofgeneticengineering,therewasanembarrassedsilence.
WhenIcamethroughthecustomsattheairport,Ihadtopay________onaclockIhadbought.
