If there were no force at the pin, g this object would be accelerated down with acceleration g, and that's not what's going to happen.

如果没有力的话，这个物体就会以加速度,往下掉，但是这,并没有发生。

youdao

Investigators scoured social networking sites such as Facebook and MySpace but initially could find no trace of him and were unable to pin down his location in Mexico.

调查人员搜寻了诸如Facebook和Myspace等社交网站，但一开始没有发现他的踪迹，也就无法确定他在墨西哥的具体藏身点。

youdao

At last we were able to pin the trouble down to a fault in the machine.

最后，我们终于找到了症结所在，是机器里面出了毛病。

youdao

Investigators also were trying to pin down whether MacInnis and the two women knew each other.

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But the data were simply not good enough to pin down what was seen.

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Both incidents were terrifying but really hard to pin down a trigger to.

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