The use of sequential reaming head for raising is a new technology, which can make a small-sized drill to be used for boring a large-sized raise.

用迈步式扩孔刀头钻凿天井是一项新技术，该技术能够用小钻机钻凿大天井。

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The grass with the fragrance of the earth in your drill out, drifts, and extinct volcanoes, tender and green flowers also stretches out his arms and yawn, small head out;

小草带着泥土的芳香钻了出来，一丛丛，一簇簇，又嫩又绿花儿也伸了伸懒腰，打了个哈欠，探出了小脑袋；

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