"What is your main job?"
Translation:Ποια είναι η βασική σου εργασία;
Τι has the meaning of "what kind..?" mostly. So, τι είναι η δουλειά σου;=what kind is your job? would get an answer like "my job is satisfing but a bit hard". But τι δουλειά κάνεις= what kind of job do you do? gets an answer "i am a dentist etc". In other questions: Τι είναι η διεύθυνσή σου; would be wrong because it has a meaning of "what kind is your address" and an expected answer is "my address is.. uh, an address". So, τι is used for asking characteristics or with the meaning of "what kind...?".
Maybe I've been running in uneducated circles, but I'm fairly certain I've heard "Τι είναι το όνομά του;" colloquially by many Greek speakers. I even asked some native family members, who, albeit are rusty, vouched for "Τι".
Are you sure it's not at least colloquially viable?
Yes, that's wrong. Because you are talking about one determined job, so the article is always going to be present with its noun. Think about this in english: "I think job tires people" (there you didn't include THE because you are talking about any job). However, "I think the job I'm doing tires me" (there you include the article THE because you are talking about one certain job, the one that you're doing)
I have to say: all lessons in this part were very difficult. It is OK to try and raise the level, but i counted about 30 new word, and difficult ones!! It is fine to teach us new difficult words but it should be much less words that it was in this part. Teach us new difficult words: six, seven, ten words.. not 30! This only makes the student tired and to lose his motivation. Thank you.
In. English, when we're talking about a person, we can either use "who" or "what". Who is your husband and what is your husband get different answers. There is no such distinction in English for objects, though.
What is your job? can get answers like "electrical engineer" or "my job is lucrative". Greek makes a distinction, though, with Ποιος and τι that can be used for both people and objects. I think some examples will show the difference:
Ποιος είναι ο άντρας σου=Who is your husband? gets an answer like "the one with the curly hair standing over there"
Ποια είναι η δουλειά σου; =what is your job? gets an answer like "nurse, electrical engineer etc"
Τι είναι ο άντρας σου=What is your husband (like)? gets an answer like "My husband is sweet and generous"
Τι είναι η δουλειά σου; = what is your job? gets an answer like "my job is well paid but tiring".
Can you see the difference between the answers given to ποιος/ποια/ποιο and τι;
Think of an object as a person. Would you use who/which one = Ποιος/ποια/ποιο or what = τι to make the same question?