How to say "not completely"?

With a negative verb, 全然 and I think also 全く have the “completely not” meaning (the English word order thing is curious, huh), and あまり is “mostly not”. How do other modifiers work here?

Depending on the sentence, I’d say that 完全に…はいない could work.

完全に壊れている → 完全に壊れてはいない

I see!

We don’t really use “completely not” in English. It’s going to be the opposite word or “not at all”. “That’s not true”, “that’s not completely true”, “that’s completely untrue”, “that’s not true at all”.

If “not completely” is rare in Japanese, I guess you can often just use an opposing expression with 少し or ちょっと. Actually, in some cases you can do that with the negative, like ちょっと分からない, but that doesn’t seem right for most things?

Searching the web for English examples (somewhat simplified):
In these areas, the risk of flooding is reduced, but not completely removed.
Even if you take all the recommended precautions, it’s not completely safe.
The rash decreased in size but did not completely resolve.
Even N95 masks could not completely block the transmission of virus droplets.
The cause of postnatal depression is not completely clear.

Searching for “完全に”, I’m starting to think that search engines have got too smart to be good for this.

Negative 完全に on Wikipedia:

金色:色だけの性質ではないので、色空間や表色系だけで完全に表すことはできない
北京語:… 方言としての北京語とは完全に同じではない。
華北:華北平原とは、多分に重なるが、必ずしも完全に一致しない。
城中村はスラムの定義と完全に符合するものではない。
核子の主要な相互作用である「強い相互作用」が未だ完全に解明されていない