So if you've ever seen or used an old school typewriter, you might recall that when you're typing something out on an old mechanical typewriter, - when you like hit the char-- when you hit the enter key to move the head back to the left hand side to the next line or you would pull down some lever, it was really a two part process.

如果你们有谁曾经看过或用过老式打字机，可能还记得，当你在,这种老式打字机上打字的时候，当你-,敲入回车键，跳转到,下一行的最左边，或者,拉一下杆，这个需要两步走。

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This focused collaboration is a key lever for driving change.

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After all, the piano is such a welter of machinery: Push a key and before you hear a note, a small lever pushes against an intermediate lever, which pushes a jack, which pushes a roller, which pushes a hammer toward the strings.

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