"The man is an engineer."
Translation:L'homme est ingénieur.
From the lesson notes:
Remember that occupations (along with nationalities and religions) can act as adjectives when used with être or devenir, so unlike in English, the French often drop the indefinite article (un, une, etc.) before an occupation.
Je suis juge. — I am a judge.
Elle va devenir avocate. — She is going to become a lawyer.
However, if any specification follows the occupation, then the indefinite article must be added.
Tu es un juge respecté par tous. — You are a judge respected by all.
Il veut devenir un professeur pour adultes. — He wants to become a teacher for adults.
Omitting the indefinite article is optional. However, if it's included in the third-person, then you must use c'est or ce sont.
C'est un juge. — He's a judge.
C’est une dentiste bien connue. — She is a well-known dentist.
Ce sont des journalistes. — They are journalists.
Hope that helps!