bend back

基本解釋

If water had a negative index of refraction, then a straw placed in a glass would appear to bend back under itself.
如果水具有負折射率，那么放在玻璃杯中的吸管似乎可能彎曲到自身下方。
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博士說，如果你能扳回拇指彎曲并觸摸到下臂，那么你腳下的韌帶也可能很有彈性。
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.
直到我們真的離開了地球，到達了大氣層，然后回過頭來看它，我們因為有限的條件是不能理解我們的星球的。

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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