$ANSWER:$

1. → This letter isn't clean enough for me to read.

    → This letter isn't too clean enough for me to read.

2. → That hat is too expensive for me to buy.

    → That hat is expensive enough for me to buy.

3. → This test is too easy for this boy to do.

    → This test is easy enough for this boy to do.

4. → These vegetables is fresh enough for us to eat.

    → These vegetables is too fresh for us to eat.

5. → This story is too interesting for you to read twice.

    → This story is interesting enough for you to read twice.

This letter is not enough clean for to read 

That hat is too expensive for me to buy

The test is too easy for this boy to do 

These vegetables is enough fresh for us to eat 

This story is enough interesting for you to read twice

cho mk cau tra loi hay nhat nhe