많은 사람들이 구분하지 않고 이 두 단어를 쓰고 있는 듯하다. 하지만 아주 똑같은 말이 아니란다.
Begin, when used as transitive verb, means "start, perform, or undergo the first part of an action or activity."
Start, when used as transitive verb, means "cause (an event or process) to happen", or "cause or enable someone or something to begin doing or pursuing something."
Martin Luther King began his speech by saying: "I am happy to join with you ..."
He started his speech which was really amazing.
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"I began to fall asleep" sounds like you're in bed expecting to drift away to sleep.
"I started to fall asleep" sounds like it was something sudden, like you were in a lecture or behind the wheel driving, and then unexpectedly passed out.