「數一數二」

(pos:形容詞)
<explanation>
yue:喺某行業、某領域嘅表現突出、成就領先，係頂尖嘅權威，唔係第一就係第二
eng:(one of) the best; leading; highly ranked; literally: counted as the first or second
<eg>
yue:佢係當今世上數一數二嘅心理學家。 (keoi5 hai6 dong1 gam1 sai3 soeng6 sou2 jat1 sou2 ji6 ge3 sam1 lei5 hok6 gaa1.)
eng:He is the world's leading psychologist.