C. Vibration strike: it is used in drilling and casing with loosen sand, cobble stone and gravel layer etc.

振动击打：用于松散的砂、卵石、碎石地层的钻进及下套管等。

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Suzugamori with sand, with the Vietnamese village girl, responding to simple and you strike up a conversation in English or Chinese can understand that many Vietnamese traditions, free shopping.

白浪触沙滩，时有淳朴的越南姑娘、小伙用简单的英文或中文与您搭讪，可了解到很多越南的风土人情，可自由购物。

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Suzugamori with sand, with the Vietnamese village girl, responding to simple and you strike up a conversation in English or Chinese can understand that many Vietnamese traditions, free shopping.

白浪触沙滩，时有淳朴的越南姑娘、小伙用简单的英文或中文与您搭讪，可了解到很多越南的风土人情，可自由购物。

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