An arc motion would make people's gaze stick to the curving hand and stay there, while a straight line would make their eyes flick back to the beginning and jump between the two.

弧形移动能使人注视弯曲的手并在移动终止点集中注意力，但直线移动会让人目光闪回起始点，并在两点间移动。

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He threw the ball back with a quick flick of the wrist.

他手腕一抖把球传了回来。

《牛津词典》

Processing plants can go back and forth between ethanol and crystallised sugar at the flick of a switch, depending on prices.

受价格影响，只要轻弹开关，加工厂就可以在乙醇和结晶糖之间转换。

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After waiting for word since a new distribution deal brought the flick back to Universal in 2008, a few months of silence hasn't broken us, but hopefully more details appear soon.

ENGADGET: E.T.: The Extra-Terrestrial Blu-ray trailer and box art pop up online (video)

The Glentoran striker's back flick at the Oval on 5 October is one of a shortlist of 10 goals in the running for the Ballon d'Or - Puskas Award.

BBC: Mattie Burrows' Glentoran goal on Fifa award shortlist

Another lovely Williams flick from the back of his hand released Muliaina to glide into the corner for a simple try - his 31st in a joint-record 92nd Test.

BBC: Scotland 3-49 New Zealand