Thank you for the compliment(s)?
He turns a pretty compliment.
He turns pretty compliments.
What’s the differences?
THX
By the way could you recommend a dictionary which can help me solve such questions?
He turns a pretty compliment - It’s a singular form ( one single compliment)
He turns pretty compliments - Plural form (he is really a polite person to do such a
thing 
You will probably solve this problm if you look into a grammar book(not a dictionary). I would reccommend E. Murphy “English Grammar In Use” (beginner/ intermediate).
Hi GS,
Where did you come across the phrase “to turn pretty compliments”? Sounds like a direct translations from another language such as Chinese. In English you usually make a compliment or you often make compliments.[YSaerTTEW443543]
TOEIC listening, photographs: At the supermarket[YSaerTTEW443543]