Can user's post in multiple local board?

Hi everyone,
I usually want to learn another language to post in other local section. But, I saw many cases, if the user post in 2 local languages, he will be suspected by hacked account or using google translator... and ended by red trust from the DT.
Example :

Quote from: MrLitex on November 30, 2017, 12:47:29 PM

The account was active from 2014 to April 2017 with Indonesian and English language.
Since November 15, 2017, this account was found in a person who writes only in Russian language.
Participates in the signature bounty of the campaign and is engaged in shitposting only.

Proof that the account is compromised:

Quote

Job4Bitcoin 2017-03-01 0.00000000 Reference Sent file contain virus

https://bitcointalk.org/index.php?action=trust;u=376479

Link to his profile:
https://bitcointalk.org/index.php?action=profile;u=376479

I know learning another language is not something very easy and simple to understand. English is not my first language, I have learned English for a long time since 2010, but still not perfect. Maybe if I learn the another language, my grammar is also not perfect. But at least I know how to write with that language and expressing what I mean.

So, can user post in multiple local board? If can, what about the user's have bad grammar? It's still allowed?
Till now I never saw members post using English language and 2 other local languages, or maybe I don't know him