The phrase "are not only valuable" is correct and usable in written English.
It is typically used in a comparative context to emphasize that something has multiple qualities or benefits, often followed by "but also" to introduce an additional quality.
Example: "These resources are not only valuable for their content but also for the insights they provide."
Alternatives: "are not just valuable" or "hold more than just value".
The big animals that the park has lost are not only valuable as tourist attractions but essential to sustaining its ecosystem.
"The movies that we make – Marvel, Pixar, Disney, Star Wars – are not only valuable brands in China, but these franchises will all have a presence eventually in this park.
Ultimately, the Obama administration needs to demonstrate that the programs are not only valuable and legal, but also that the government's use of that data can be constrained and verified.
These results are not only valuable to the engineering design of flexible and protective shells, but also have implications on the mechanics of fish swimming.
It is suggested that online photographs and blogs are not only valuable information sources for potential visitors, but also an effective way to understand the Chinese market.
A wide variety of LAB from traditional Egyptian dairy products that showed potentially important properties are not only valuable for practical application but they may also provide an expanded gene pool for designing genetic modified strains with improved traits.
Ms. Paul's examples of better homework assignments like those using "spaced repetition" and "retrieval practice" aren't only valuable homework assignments; they would also teach students how to study.
"It's not only valuable property, but it's pivotal in statewide politics".
The task force found that they were not only valuable in reducing deaths from colorectal cancer but also cost-effective.
Because the collection is not only valuable but also fragile, Mrs. Erenberg is the only one who dusts the pieces, which she does once a week for about two hours, she said.
We have to decide as a country — politicians and parents, corporations and communities — that high-performance education is not only valuable to our sense of self, but essential to our future prosperity.
