1. As he was young, he liked playing soccer.
2. When he was young, he liked playing soccer.
3. Because he was young, he liked playing soccer.
4. As he was young, he couldn't work at a company.
5. When he was young, he couldn't work at a company.
6. Because he was young, he couldn't work at a company.
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Thank you for your help.
'As' has too many meanings. Does #1 mean #2 or #3?
Does #4 mean #5 or #6?
2, 3, 5, and 6 are the best sentences here.
You're right that "as" has too many meanings. It's best to skip it and use one of the others, whichever makes sense in your sentence.