fluctuate困难

Their intensity has vastly fluctuated.

它们的强度大幅波动。

“For decades we have not taken responsibility for investing in our domestic wood supply, leaving us exposed to fluctuating prices and fighting for future supplies of wood as global demand rises and our own supplies fall.”

“几十年来，我们一直没有承担起投资国内木材供应的责任，导致我们在全球需求上升、自身供应下降之际，暴露于价格波动之中，并不得不争夺未来的木材供应。”

The UK’s exposure to fluctuating wood prices is a result of ____

英国受到木材价格波动的影响是由于____

[However], because these connections are made through effort and practice, scientists believe that intelligence can expand and fluctuate [according to] mental effort.

然而，由于这些联系是通过努力和练习建立起来的，科学家们认为智力会随着脑力投入的多少而增长和波动。

fluctuate

波动