Question

which lines from mending wall best indicate that the speaker is amused while repairing the wall? we wear our fingers rough with handling them. oh, just another kind of out - door game, no one has seen them made or heard them made, but at spring mending - time we find them there. and he likes having thought of it so well he says again, \good fences make good neighbours.\ we have to use a spell to make them balance: \stay where you are until our backs are turned!\

Explanation:

The line "Oh, just another kind of out - door game" and the idea of using a "spell" to make the stones balance and stay in place show a light - hearted, amused tone. The comparison to a game and the whimsical idea of a spell suggest the speaker finds the activity somewhat humorous.

Answer:

We wear our fingers rough with handling them.
Oh, just another kind of out - door game,
We have to use a spell to make them balance
"Stay where you are until our backs are turned!"