一、口算。
$4+13=$
$10-10=$
$8+2+5=$
$15-5=$
$10-8=$
$12+2+5=$
$14+5=$
$14-3=$
$17-6+4=$
$10-9=$
$15-2=$
$14-2-2=$
$6+2=$
$12+1=$
$17-5-2=$
$11+3=$
$12+5=$
$11+5+2=$
$19-4=$
$3+11=$
$13+3-5=$
$12-10=$
$17-10=$
$14-3+8=$
$13-10=$
$18+1=$
$18-4-3=$
$2+15=$
$15+2=$
$7-4+3=$

1.15 2.14 3.11
4.2 5.7 6.19
7.3 8.19 9.11
10.17 11.17 12.6

二、算一算，填一填。

1.16 2.17 3.11 4.19 5.13
6.11 7.8 8.14 9.13 10.12
11.19 12.13 13.16 14.17 15.18