Answer:
sullen
Explanation:
Sullen can be defined as bad-tempered and sulky; gloomy.
The English language has a variety of many grammatical inferences mainly because our language is more complex and is used as a national language. Such a selection of words, spellings etc are used so many can refer to a situation with grammar they can understand.
It should read COMPLIMENTARY ADMISSION FOR TEACHERS AND STUDENTS in other words it means that for teachers and students admission is free or "compliments of the house" as the saying goes. Complementary means on the contrary that the teachers and students complement or support each other.