【单选题】I never seem to lose any weight, __________I try hard.
【单选题】Mr. Black has been teaching English in a middle school _____ he came to China.
【简答题】已知△ABC,∠B=60°,且sinA-sinC+ 2 2 cos(A-C)= 2 2 .求sinC的值.
【单选题】______ you have finished your work, you are free to do what you like.
【单选题】—How long have you been working as an assistant here? —__________I finished middle school.
【单选题】You must be strict with your children _____________.
【简答题】△ABC中,若(sinA+sinB+sinC)(sinA+sinB-sinC)=3sinAsinB,则C=______.