4+1= 4-2= 1+3= 2+2=
5-3= 2+3= 5-1= 3-1=
1+1= 5-2= 3+2= 5-4=
2+1= 4-3= 1+4= 4-1=
4+□=□
□+□=□
4-□=□
□-□=□
(只)
>5 10= <2 8>
8+411 8+213-3
220 18-107 8+7 7+7
比多。( )