You wold drop the ending -er and replace it for -o -as -a -emos -áis -an if your conjugating it in the present tense if your conjugating it in the past tense then it's
-í -iste -ió -imos -isteis -ieron
Cecilia is la hija ......
For this case, what we should do is select the grammatical structure correctly.
In English, we have that the correct sentence is given by:
The student works nervous
We observe that we have:
Subject: the student
verb: work
Predicate: nervous
Therefore, in Spanish the correct structure is:
El estudiante trabaja nervioso
Answer:
El estudiante trabaja nervioso