الجَمْعThe plural

Nouns are made plural in any of the following ways:

Adding the suffixes ون or ين to the end of the singular masculine noun. This kind of plural is called: the regular or sound  masculine  plural: طيب ←  طيبـون، طيبـين/ معلم ←  معلمـون، مُعَلِّمِـينَ

Adding the suffix ات to the end of the singular feminine noun. This kind of plural is called: the regular or sound  feminine plural: طيبة←  طيبـات/ معلمة←  معلمـات

This rule is true also for some masculine singular nouns : تَرْتِيب ← تَرْتِيبـات/ اسْتِقْبال ← اسْتِقْبالـات

Changing the form of the singular masculine or feminine noun. This kind of plural is called: the irregular or broken plural it has no given rule: رجل ← رجال / غُرْفة ← غُرَف