The laws of physics are considered unchangeable, yet scientific theories about them are constantly refined through new experiments.
物理定律被认为是不可改变的，然而关于它们的科学理论通过新实验不断得到完善。
Which choice best defines “unchangeable”?
C — Not able to be changed. “unchangeable” means not able to be changed.
Which word means “not able to be changed”?
C — unchangeable. “unchangeable” means not able to be changed.
unchangeable — not able to be changed. In Chinese: 不可改变的.
unchangeable is pronounced /ʌnˈtʃeɪndʒəbl/.
The laws of physics are considered unchangeable, yet scientific theories about them are constantly refined through new experiments. (物理定律被认为是不可改变的，然而关于它们的科学理论通过新实验不断得到完善。)
immutable, fixed, unalterable — all close in meaning to unchangeable (not able to be changed).
changeable, mutable — each the opposite of unchangeable (not able to be changed).
Yes. unchangeable is on the SAT Prep Basic list — the everyday academic words the SAT assumes you already have. The Digital SAT does not test vocabulary in isolation; words like this one are tested through Words in Context questions, where you choose the word that completes a passage most logically and precisely.