I think the meaning is “I became an advocate” or similar.
I think, “advocate” like “became” is also a verb, but what is the special meaning that “became and advocate” has, while “became an advocate” doesn’t have.
I am an English learner.
Your help will be much appreciated.
Data from:
TED: Immigrants voices make democracy stronger
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So I started a career as a social entrepreneur, starting an organization for young people like myself -- I was young at the time that I started it -- who traced their heritage to the Indian subcontinent.
In that work, I became and advocate for South Asians and other immigrants.
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