$\frac{5}{7}-\frac{2}{3}=$

Step 1 ：First, we need to find a common denominator for the two fractions, which is 21.

Step 2 ：Convert both fractions to have this common denominator and then subtract them: \(\frac{5}{7}=\frac{15}{21}\) and \(\frac{2}{3}=\frac{14}{21}\).

Step 3 ：Subtract the two fractions: \(\frac{15}{21}-\frac{14}{21}=\frac{1}{21}\).

Step 4 ：Final Answer: \(\boxed{\frac{1}{21}}\)