[Originally posted on 03/25/15 on the Duolingo Turkish for English speakers forum by AlexinNotTurkey]
Forming the plural in Turkish is simple compared to the Accusative case. It is formed using the suffix -lAr. Now you might be thinking, “what is that capital A doing there?” to which we respond with 2-way vowel harmony.
This is the other form of vowel harmony found in Turkey suffixes. Basically if the final vowel is front (i, e, ü, ö) use -ler. If it is back (a, ı, o, u), use the suffix -lar. This rule along with the rule for four way vowel harmony will be used in several suffixes across Turkish grammar, so try to get used to it now.
Here are some examples:
[Updated by Danika_Dakika starting 03/01/22]
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