Try to change them to the same denominator. Denominators are the same, the numerator is large and the numerator is small. For example, the denominators of 1/5 and 3/5 are both 5, and 3/5 is greater than 1/5. Use numerator, the number with small denominator is large, and the number with large denominator is small. For example, 2/7 and 2/9, the numerator is 2, the denominator is 7 and 9 respectively, and 7 is less than 9, so 2/7 is greater than 2/9.