4. 计算：
(1) $\left| -\dfrac{1}{4} \right| + \dfrac{5}{6} - ( -\dfrac{2}{3} ) - \dfrac{1}{2}$；
(2) $2.17 - 39 - (-17.83) - [ 8\dfrac{7}{8} - ( -1\dfrac{5}{8} ) ]$；
(3) $\left| \dfrac{4}{7} - \dfrac{2}{5} \right| - \left| \dfrac{3}{5} - \dfrac{7}{9} \right| + \left| \dfrac{2}{9} - \dfrac{3}{7} \right|$；
(4) $-( -\dfrac{3}{2} ) + ( -\dfrac{5}{6} ) + [ \dfrac{11}{4} - ( -\dfrac{3}{8} ) - ( +\dfrac{14}{3} ) ]$；
(5) $-2\dfrac{1}{3} - [ -( -1\dfrac{2}{3} - 0.4 ) ] + ( -1\dfrac{1}{5} )$；
(6) $\left| -4\dfrac{1}{8} \right| - | -0.125 | - \left| -3\dfrac{1}{3} \right| - ( -6\dfrac{1}{5} ) + ( -5\dfrac{1}{5} )$。

(1) $\dfrac{5}{4}$
(2) $-29\dfrac{1}{2}$
(3) $\dfrac{1}{5}$
(4) $-\dfrac{7}{8}$
(5) $-5\dfrac{3}{5}$
(6) $1\dfrac{2}{3}$

5. 计算：
(1) $(-18) ÷ (-\dfrac{2}{3})$；
(2) $16 ÷ (-\dfrac{4}{3}) ÷ (-\dfrac{9}{8})$；
(3) $(-\dfrac{7}{5}) × (-2) × (-3\dfrac{4}{7}) × 3.5$；
(4) $(-24) × (\dfrac{1}{2} + \dfrac{5}{6} - \dfrac{7}{12})$；
(5) $(-\dfrac{2}{3} + \dfrac{1}{6} - \dfrac{3}{8}) ÷ (-\dfrac{1}{24})$；
(6) $(-\dfrac{5}{11}) × \left| -\dfrac{8}{13} \right| × (-2.2) × (-1\dfrac{3}{4})$；
(7) $(-15) ÷ [ (-2) × 3 ÷ 9 ]$；
(8) $99\dfrac{7}{8} × (-4) - (\dfrac{1}{2} - \dfrac{1}{3} - \dfrac{5}{6}) × 24$；

(1) 27
(2) $\dfrac{32}{3}$
(3) -35
(4) -18
(5) 21
(6) $-\dfrac{14}{13}$
(7) $\dfrac{45}{2}$
(8) $-383\dfrac{1}{2}$