Grammar - NI
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Anyway, ni tells that the word or sentence before is the topic for the next words or sentences. You will see this used in commentaries where a word is defined, so first you have the word, then ni, then the definition. It's also used in verses as a filler syllable to achive seven-syllable verses (as in Abhidharma-kosha the Tibetan version).
Examples:
sangs rgyas ni - buddhas, they...
de ni - that (that, it is....)
'di ni - this, (this, it is)
las ni - karma, it is...
stong pa nyid ni - emptiness, it is...
snying rje chen po ni - great compassion, that is
Usually you find a better word or structure for the actual translation, but you could always use a filler word set such as 'that is' to get a start on the translation