It means that when you achieve the level or get to a point were you become th master of something in your career.
Answer: thorough
Explanation:
B) Declarative is the answer.
I don't see the underline, but I'm pretty sure that the verb is "has known". That's the present perfect tense.
Answer:
Give/send, read/open
Explanation:
Because the only two possible words for those incomplete sentences are those one ms i filled in with
