Better , bettering , bettered

'To better' is a verb formed from the comparative adjective. It means 'to improve one's knowledge, experience or prospects'. It works just like any other regular transitive verb and is nearly always used in the reflexive (with '___self' as the object of the verb) - "I better myself", &c. "I bettered myself by taking a course in Computing" is in the past tense "I would be bettering myself ..." ["if I did something" or "by doing something"] is in the conditional tense (usually followed by "if" or "when" or another condition). "I am bettering myself" is in the present continuous tense - describing some action which is continuing now. It is not to be confused with the use of 'better' in the idiom "I had better [do something]" meaning "I ought to ..." or "I should ...", for example: "I had better not talk any longer or I shall be late for my appointment"

Sorry - I missed that you asked for sentences. Some examples might be: I am bettering myself by exercising. Scientists are working on bettering our understanding of animals. I would be bettering myself if I ate healthier. I bettered myself by reading about car care. Microsoft bettered Windows with the introduction of Windows 8. Basically, you could almost always substitue the word improve (or the proper conjugation of improve)for the verb form better. It's often used when referring to oneself, but not always.

I think the confusion comes in because we generally use the word better as an adjective or adverb. Like if we say one thing is better than another. It's usually used to compare things. But when you conjugate the word, better has to be used as a verb. In this case, better refers to improving something. Like if we say I took college classes to better myself. You just don't hear this use of the word as often as you do the first way.