As a matter of grammar, yes. If you want to have friends, then no.
Using plain language with strangers can be considered rude because it’s too intimate and has no distance or formality.
On the flip side, using formal language with friends can be considered rude or ‘cold’ because it imposes distance and formality.
In meaning, however, they are largely the same, desu can always be used in place of da, dewa arimasen can always be used in place of ja nai.
(da cannot always be used in place of desu, though, in particular i-adjective sentences, ‘furui desu’, the plain sentence is just ‘furui’. ‘desu’ is added only as a marker of formality here, not for meaning.)
1 comment
As a matter of grammar, yes. If you want to have friends, then no.
Using plain language with strangers can be considered rude because it’s too intimate and has no distance or formality.
On the flip side, using formal language with friends can be considered rude or ‘cold’ because it imposes distance and formality.
In meaning, however, they are largely the same, desu can always be used in place of da, dewa arimasen can always be used in place of ja nai.
(da cannot always be used in place of desu, though, in particular i-adjective sentences, ‘furui desu’, the plain sentence is just ‘furui’. ‘desu’ is added only as a marker of formality here, not for meaning.)