Doubling syllables in adjectives?

[Daxx]

I've seen words like these:

平平坦坦(的)

明明白白(的)

开开心心(的)

Do they mean the same as 平坦(的), 明白(的) and 开心(的)??

If yes, what is the point of using the doubled ones?

Thanks.

[andysun731]

They mean the same. Doubling-syllables adjectives are used to exaggerate atmosphere in context, to be rhythmic, or to be vivid.

[chaiknees]

Reduplicated adjectives can have different functions:

1. As predicate, the function is descriptive: 他个子高高的，大家都高高兴兴的，这个消息确确实实的
   
2. As complement, it indicates a high degree: 君子兰的叶子长得长长的
   
3. As attribute, it can be descriptive and also indicate a high degree, it often has a positive meaning: 漂漂亮亮的客厅，这个地方有红红的花儿
   
4. As adverbial, it indicates a high degree: 整整齐齐地排队，安安静静地看书，热热闹闹地过春节，清清楚楚地告诉我，痛痛快快地分手
   

[Daxx]

Thank you