D is CAM wheel pole driving, spring automatic restore structure, tight structure, reasonable design, stable driving, dust discharge and dependable air lock.

D为凸轮连杆传动，弹簧自动复位机构，结构紧凑、设计合理、运转平稳，卸灰、锁气可靠。

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The fit of all pieces and mechanisms of each knife is tight and smooth and lock up was solid.

每把刀的所有部分和机制都安装紧密而光滑，并且用固体锁上。

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For each exercise, be sure to warm up first, keep abs tight, breathe, and not lock elbows or knees.

每次练习都要先做热身，收腹，调整呼吸，并且肘部和膝盖不能弯曲锁定。

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The parasite anchors itself to the slippery surface of the host intestine using micro-needle tips that pierce the surface and then, once wet, swell to lock tight.

BBC: 'Bed-of-needles' super-grip plaster for surgical wounds