Adverbs of degree 格外 and 极其
Adverbs of degree (程度副词) are used to intensify or modify the degree of an adjective (or verb): very, really, extremely.
The adverb 格外
格外 
is placed before a predicate which is expressed either by an adjective or a verb.
格外 can be followed by the particle 地 .
is placed before a predicate which is expressed either by an adjective or a verb.
格外 can be followed by the particle 地 .Examples
大家认为那里的形势格外地好
Everyone thinks the situation there is particularly good
dàjiā rènwéi nàlǐ de xíngshì géwài de hǎo
他对计算机格外感兴趣
He is especially interested in computers
tā duì jìsuànjī géwài gănxīngqù
她是个格外聪明的女人
She is an incredibly smart woman
tā shì ge géwài cōngmíng de nǚrén
The adverb 极其
极其 is only placed before two-syllable adjectives and verbs.
is only placed before two-syllable adjectives and verbs. Pay attention
Two-syllable words are words that consist of two characters.
Examples
他的病极其严重，必须马上做手术
His illness is extremely serious and he must have surgery at once
tā de bìng jíqí yánzhòng, bìxū mǎshàng zuò shǒushù
各国政府极其重视环境保护问题
All national governments attach great importance to environmental issues
gè guó zhèngfǔ jíqí zhòngshì huánjìng bǎohù wèntí
他是一个极其讨厌的家伙
He's an extremely annoying guy
tā shì yí ge jíqí tǎoyàn de jiāhuo