Collocations for inappropriate - adj.

be, seem
become
make sth
The size of the machines makes them inappropriate for domestic use.

consider sth, feel sth, judge sth, regard sth as, see sth as, think sth
It was felt inappropriate by some that such a serious occasion should include dancing.

extremely, fairly, very, etc.
highly, particularly, singularly (esp. BrE), wildly
This treatment was highly inappropriate in her case.

completely, entirely, quite (esp. BrE), totally, utterly (esp. BrE), wholly (esp. BrE)
increasingly
clearly
culturally, sexually, socially

for
Your bright red coat would be quite inappropriate for a funeral.

to
The existing library is totally inappropriate to our needs.

Inappropriate is used with these nouns:
behaviour, conduct, remark, response, use