[General] by myself/for myself

[yeju]

I wonder the difference in meaning between 'by myself' and 'for myself'.

Sentences are here.
1.I did it by myself.
2.I did it for myself.

Does by myself in the 1.sentence mean alone?

 

[jutfrank]

I did it by myself means I did it alone, or without help.

I did it for myself suggests nobody else asked me to do it.

 

[GoesStation]

Yes, it does.

 

[teechar]

I wonder about the difference in meaning between 'by myself' and 'for myself' in the following sentences. [STRIKE]are here.[/STRIKE]
1. I did it by myself.
2. I did it for myself.

Does by myself in the first sentence mean alone?

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