A:②①③④
B:②④③①
C:④②③①
D:④③①②
My uncle is a(n) ________. He works in a restaurant near my home.
—Yeah, it _____ us a whole year to finish the work.
已知曲线C1:y=cosx,C2:y=sin(2x+ 2π3 ),则下面结论正确的是( )