So I was doing a bit of writing and ended up using the phrase "long-thought" (as in, "a technique long-thought forgotten" or "people long-thought incapable of using magic"). I ended up using it quite a few times and was wondering if anyone can come up with another phrase with the same (or a very similar) meaning so that I won't constantly be using the same word. Thanks to anyone who can help!
Synonyms to the rescue. The term is Believed to be. The Coelacanth was believed to be extinct until one showed up off the coast of Madagascar.
Received knowledge was that Trump was not a serious candidate.
I learned this phrase from listening to BBC news programs. It means what was popularly believed.
You can also use that: popularly believed. For example:
At one time, it was popularly believed that Mars was criss-crossed with canals.
The common or popular conception was that etc.
You can also try
people previously thought [to be] incapable of using magic
In other words, leave out "long." (This "to be" is optional.)