想象一下不用水泥或钉子建一所房子。
Just imagine building a house without cement or nails to hold together.
在旧中国，我们连一个钉子都造不了，更不用说制造机器了。
In old China we could not make a nail, let along (make) machines.
在旧中国，我们连一个钉子都造不了，更不用说制造机器了。%。
In old China we could not make a nail, let alone (make) machines.
在旧中国，我们连一个钉子都造不了，更不用说制造机器了。
In the old China, we can't even make a nail, let alone machines.
在旧中国，我们连一个钉子都造不了，更不用说制造机器了。
In the old China, we can't even make a nail, let alone machines.
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