Question

1. I've spent all my money already.
2. She spent ¡Ì100 on a new dress.
3. I've used all my money already.
4. She used ¡Ì100 on a new dress.
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Can we use both 'spent' and 'used' in the sentences?

5. I used up my allowance in two days.
6. I didn't want to break up with her.
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Does 'up' mean 'completely' in each sentence?

Answer 1

In 3 and 4, I'd include "up" -- to use up something means it's all gone. In this case, you're referring to money. But 1, 2, 3, and 4 are not completely interchangeable.

In 5, yes, the word "up" means completely.

In 6, "up" is just part of that phrasal verb that means they ended their relationship.