12. The size order of $\sin 1, \sin 2, \sin 3, \sin 4, \sin 6$ is $\qquad$
$\begin{array}{l}\text { 12. } \sin 2>\sin 1>\sin 3>\sin 6>\sin 4 \text {. } \\ \sin 2=\sin (\pi-2)>\sin 1>\sin (\pi-3)=\sin 3>0>\sin 6=-\sin (2 \pi-6)>-\sin (4- \\ \pi)=\sin 4 \text {. }\end{array}$