score:3
The Pali suttas define three types of 'becoming', as follows:
And what is becoming? There are three kinds of becoming: sensual becoming, fine-material becoming & immaterial becoming. This is called becoming. ~ SN 12.2 ~
In AN 3.76, ‘becoming’ (bhava) is defined as the mind "established" in a sense object:
“the consciousness of beings (sattānaṃ), hindered by ignorance and bound by craving, that is established (patiṭṭhitaṃ) in the sensuality, materiality or immateriality element/sphere”
Therefore, these three types of becoming simply reflect the levels of sustained & continued attachment to: (i) the physical body and its sensations; (ii) attachment to fine-material states of meditative absorption (rupa jhana); and (iii) attachment to the immaterial states of meditative absorption (arupa jhana).
For example, the mind of a man sees (has sense contact with) a certain woman (sense object) and due to pleasant feelings & craving/lust towards the woman, the male mind gets stuck on or "picks up"/"carries" the sense object in his mind & starts thinking about the woman. This beginning to be mentally pre-occupied with the woman is attachment or grasping (upadana). The male mind then becomes fixated or obsessed with the woman, falling in love, thinking about the woman all the time & dreaming about how they will live romantically forever. This continued establishing & transforming of the mind in relation to the sense object is "becoming". Then the man & woman have a marriage ceremony and the man "becomes" the woman's husband and the woman "becomes" the man's wife. The marriage ceremony is "becoming" and the finality of actually being a "husband" or being a "wife" is called "birth" ("jati").
"Jati" ("birth") is defined as the mental creation of the ideas or social conventions of "beings" & the "various orders of beings", such as "man", "woman", "husband", "wife", "lawyer", "doctor", "me", "you" etc.
Therefore, in summary, 'becoming' is just the continuation of 'attachment', however more intensely, to the point that the mind 'transforms' itself into something different to what is was previously.