How do Tibeto-Burman languages create grammatical markers from ordinary nouns and verbs?

In Tibeto-Burman languages, abstract grammatical relationships are often expressed by specializing full nouns and verbs through a process of semantic bleaching. As these words lose their original, specific meanings, they evolve into functional markers.1

• Verbs: Words originally meaning actions such as "give," "dwell," "put," or "finish" are repurposed to serve as markers for verbal categories like causative, progressive, durative, and completive aspects.1
• Nouns: Nouns can be transformed into grammatical particles. For example, a noun meaning "road" may become a locative particle, while one meaning "top part" can evolve into an accusative marker.1

This specialization is often accompanied by phonological changes, such as destressing or the acquisition of a specific tone, which distinguishes the new grammatical particle from the original root word. In some cases, such as in Loloish languages, multiple verbs may be concatenated, where one acts as the semantic head while others are grammaticalized to modify it.1