自然数集 zì rán shù jí

DEFINITIONS

  1. the set of natural numbers (math.)

CHARACTERS

自 zì
HSK 3
self, private, personal; from
然 rán
HSK 2
yes, certainly; pledge, promise
数 shù
HSK 3
number; several, count; fate
集 jí
HSK 5
assemble, collect together