\(\dfrac{3}{4}+\dfrac{1}{3}-\left(\dfrac{7}{4}-\dfrac{5}{3}+\dfrac{3}{7}\right)\\ =\dfrac{3}{4}+\dfrac{1}{3}-\dfrac{7}{4}+\dfrac{5}{3}-\dfrac{3}{7}\\ =\left(\dfrac{3}{4}-\dfrac{7}{4}\right)+\left(\dfrac{1}{3}+\dfrac{5}{3}\right)-\dfrac{3}{7}\\ =-1+2-\dfrac{3}{7}\\ =1-\dfrac{3}{7}\\ =\dfrac{4}{7}.\)