When they repeatedly stretched and relaxed the material, without breaking it, it only turned a little red.

当他们在不把材料弄破的前提下，反复拉伸时，材料只是稍微泛红而已。

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When they repeatedly stretched and relaxed the material, without breaking it, it only turned a little red.

当他们在不把材料弄破的前提下，反复拉伸时，材料只是稍微泛红而已。

youdao