一、口算。
$\frac{11}{8}-\frac{1}{8}=$ $\frac{11}{10}+\frac{3}{10}=$ $\frac{25}{36}+\frac{11}{36}=$
$\frac{19}{36}+\frac{13}{36}=$ $\frac{10}{7}-\frac{6}{7}=$ $\frac{7}{9}-\frac{1}{9}=$
$\frac{14}{15}-\frac{3}{15}=$ $\frac{17}{9}+\frac{11}{9}=$ $\frac{17}{10}-\frac{3}{10}=$
$\frac{11}{8}+\frac{7}{8}=$ $\frac{12}{14}-\frac{7}{14}=$ $\frac{2}{6}+\frac{3}{6}=$
$\frac{1}{5}+\frac{14}{5}=$ $\frac{9}{16}+\frac{8}{16}=$ $\frac{17}{9}-\frac{2}{9}=$
$\frac{12}{13}-\frac{3}{13}=$ $\frac{5}{8}+\frac{1}{8}=$ $\frac{3}{7}+\frac{6}{7}=$
$\frac{5}{16}-\frac{1}{16}=$ $\frac{11}{25}+\frac{13}{25}=$ $\frac{5}{14}+\frac{1}{14}=$
$\frac{5}{23}+\frac{12}{23}=$ $\frac{11}{12}-\frac{1}{12}=$ $\frac{10}{19}-\frac{4}{19}=$
$\frac{16}{31}-\frac{7}{31}=$ $\frac{4}{21}+\frac{12}{21}=$ $\frac{17}{18}+\frac{1}{18}=$
$\frac{16}{42}+\frac{19}{42}=$ $\frac{35}{36}-\frac{18}{36}=$ $\frac{8}{11}-\frac{6}{11}=$

$\frac{5}{4}$
$\frac{7}{5}$
1
$\frac{8}{9}$
$\frac{4}{7}$
$\frac{2}{3}$
$\frac{11}{15}$
$\frac{28}{9}$
$\frac{7}{5}$
$\frac{9}{4}$
$\frac{5}{14}$
$\frac{5}{6}$
3
$\frac{17}{16}$
$\frac{5}{3}$
$\frac{9}{13}$
$\frac{3}{4}$
$\frac{9}{7}$
$\frac{1}{4}$
$\frac{24}{25}$
$\frac{3}{7}$
$\frac{17}{23}$
$\frac{5}{6}$
$\frac{6}{19}$
$\frac{9}{31}$
$\frac{16}{21}$
1
$\frac{5}{6}$
$\frac{17}{36}$
$\frac{2}{11}$