ลงไป(long bpai)

[to] go down; descend (away)

to move from a higher place to a lower place, away from the speaker or reference point

directional particle: down/into (away)

used after a verb to show movement downward or into something, away from the speaker (e.g., วางลงไป put it down; ใส่ลงไป put it in)

and below; downward from (a point)

used after numerals, measures, or a stated point to mean “and below” or “from this point downward” (e.g., อายุอายุaa-yú1age2lifespan; service life3[to] be X years old 12 ปีลงไป = age 12 and under; ตั้งแต่นี้ลงไป = from here downward/onward in the text)