自然数集

the set of natural numbers (math.)

to gather / to collect / collected works / classifier for sections of a TV series etc: episode

self / oneself / from / since / naturally / surely

to count / to count as / to regard as / to enumerate (sb's shortcomings)

number / figure / several / CL:個|个[ge4]

frequently / repeatedly

nature / natural / naturally

correct / right / so / thus / like this / -ly

natural number