"Now let's see if you can lay shingles. Pick out one that you think will be right to cover the crack in the row beneath, and lay it down close up to the last one and with its thick edge to that blue line."
David was rather excited at the thought that he was to lay the shingles.
"Shall I?" he asked.
The foreman nodded, and he pointed to a shingle.
"Try that one."
So David took the one that the foreman pointed at, and he laid it down as well as he could, close up to the last one which the shingle man had put on, and with its thick edge at the blue line.
It took him some time, because he had never laid shingles before; but the shingle man had only to change it a tiny bit, and then he drove in two nails about halfway up toward the thin edge.
And David took another shingle which the foreman pointed at, and he fitted it in its place a little more quickly, and the shingle man didn't have to change that one at all, but drove the nails with hardly more than two blows of his hammer.
So David kept on laying shingles, and the shingle man nailed them.
At first the foreman pointed to the right shingles; but, after a while, he didn't point, but David chose them himself.