for or by

[Mike12345]

1 As a teenager, perhaps your parents don't trust you to make decisions for yourself yet, but their trust can be earned.
2 As a teenager, perhaps your parents don't trust you to make decisions by yourself yet, but their trust can be earned.

I think "for" and "by" are both correct in this sentence. But the answer given in the book is "for". Am I wrong? Could you please tell me your opinion? Thank you!

 

[Rover_KE]

What book?

Always tell us the source and author of any text you quote, please.

 

[Mike12345]

What book?

Always tell us the source and author of any text you quote, please.

五年高考三年模拟 Exercise book

 

[Matthew Wai]

五年高考三年模拟

A literal translation: 'Five years of A level exams. Three years of mocks.'

 

[Mike12345]

A literal translation: 'Five years of A level exams. Three years of mocks.'

Because my English is so poor, I can't translate the name into English. So I am only able to write Chinese for Teacher Rover KE.

 

[teechar]

That sentence is not well phrased. To answer your question, both "for" and "by" are indeed possible, but they don't necessarily mean the same thing.

 

[Matthew Wai]

Make a decision for yourself—the decision is intended for you.
Make a decision by yourself—you are the one who makes the decision.