To evaluate the expressions, we perform the operations step by step:

1) 2 3/8 + 1 5/6
= 6/8 + 5/6
= 6/8 + 4/8
= 10/8
= 5/4
= 1.25

2) 4 3/8 + 8 1/2
= 12/8 + 8/2
= 12/8 + 4
= 12/8 + 32/8
= 44/8
= 11/2
= 5.5

3) 4 2/5 + 9 3/7
= 8/5 + 27/7
= 56/35 + 135/35
= 191/35
≈ 5.4571

Therefore, the evaluated expressions are:
1) 2 3/8 + 1 5/6 = 1.25
2) 4 3/8 + 8 1/2 = 5.5
3) 4 2/5 + 9 3/7 ≈ 5.4571