bend back

基本解释

If water had a negative index of refraction, then a straw placed in a glass would appear to bend back under itself.
如果水具有负折射率，那么放在玻璃杯中的吸管似乎可能弯曲到自身下方。
If you can bend back your thumb to touch your lower arm, the ligaments in your feet are probably stretchy, too, Dr. Gastwirth said.
Gastwirth博士说，如果你能扳回拇指弯曲并触摸到下臂，那么你脚下的韧带也可能很有弹性。
It wasn't until we really left Earth, got above the atmosphere and had seen the horizon bend back on itself that we could understand our planet as a limited condition.
直到我们真的离开了地球，到达了大气层，然后回过头来看它，我们因为有限的条件是不能理解我们的星球的。

In his book, Mr Sen raised the theoretical possibility that a pastoralist's supply curve might actually bend back on itself: as the relative price of livestock falls, a hungry pastoralist might supply more animals to the market, not fewer as elementary economic principles would imply.
ECONOMIST: Economics focus
Then, at the same place, bend it back to form a right-angle in the opposite direction.
ECONOMIST: Aircraft fatigue
He asks me to help him into a back-bend by using my ankles for support.
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