The adverb of degree 蛮
Adverbs of degree (程度副词) are used to intensify or modify the degree of an adjective (or verb): very, really, extremely.
We use the adverb 蛮 
to express the degree of a feeling or an attribute.
We should state it before a predicate which can be expressed by an adjective or a verb.
to express the degree of a feeling or an attribute.
We should state it before a predicate which can be expressed by an adjective or a verb.Scheme
蛮
adjective/verb
Pay attention
We most often use 蛮 in colloquial speech.
Examples
她的分数蛮高的，大学肯定能考上
Her score is quite high, she can definitely get into college
tā de fēnshù mán gāo de, dàxué kěndìng néng kǎo shàng
他俩的关系蛮不错
The relationship between them is quite good
tā liǎ de guānxì mán búcuò
这项商品似乎蛮有前景的
This product seems to be quite promising
zhè xiàng shāngpǐn sìhū mán yǒu qiánjǐng de