You don't have to submit a template resume, but you can also introduce yourself in writing (this is usually called a cover letter), but it's not too long. You can vote for both because the recruiter won't have much time to read your cover letter, so it's better to be simple and clear. It won't leave you the impression that what you say is informal and irregular. Generally speaking, there is no possibility that a work will be stolen by a company. If he takes a fancy to your work, he will basically use you. But in order to protect his rights, you can keep a sample of the work and report it to the relevant department after you find it. Even bring a lawsuit to the court.

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