English grammar rule To non base

For verbs, the “root” is its basic form. When forming the infinitive, add to- to the verb root. Keep in mind that the same verb can take on many forms, but the root never changes.

Examples of 'To non base' rule

Incorrect	Alex is unable to choosing the book.
Correct	Alex is unable to choose the book.
Incorrect	Diana hopes to improves her score.
Correct	Diana hopes to improve her score.