At every two feet which the hole gained in depth they successively withdrew the blocks.

每次掘到二英尺深，他们就陆陆续续地把支架抽出来。

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At every two feet which the hole gained in depth they successively withdrew the blocks.

每次掘到二英尺深，他们就陆陆续续地把支架抽出来。

youdao