Expressing "especially" with 专门 and 专程
Both adverbs have the same meaning, but differ slightly in usage.
The adverb 专程
专程 
emphasizes that a person has come somewhere for a purpose.
emphasizes that a person has come somewhere for a purpose.Examples
我是专程来这看你的
I came here just to see you
wǒ shì zhuānchéng lái zhè kàn nǐ de
是的，这次是专程来玩
Yes, this time I came especially to have fun
shì de, zhè cì shì zhuānchéng lái wán
他是专程来这里拜访她们的
He came here to visit them
tā shì zhuānchéng lái zhèlǐ bàifǎng tāmen de
The adverb 专门
The adverb 专门 has the following two meanings:
1) "especially", "specially".
It emphasizes that a person has come somewhere or done something for a purpose.
has the following two meanings:
1) "especially", "specially".
It emphasizes that a person has come somewhere or done something for a purpose.Examples
我将专门派人送这笔钱
I will get someone to send this money
wǒ jiāng zhuānmén pài rén sòng zhè bǐ qián
我委托他专门为你画点什么
I asked him to draw something just for you
wǒ wěituō tā zhuānmén wèi nǐ huà diǎn shénme
我来北京是专门为了看你的
I came to Beijing just to see you
wǒ lái běijīng shì zhuānmén wèi le kàn nǐ de
2) "on purpose", "only".
In this meaning, it emphasizes that an action had a specific purpose.
Examples
这次开会专门讨论了公司的工人的问题
This meeting was devoted to the issue of the company's workers
zhè cì kāihuì zhuānmén tǎolùn le gōngsī de gōngrén de wèntí
这座塔是专门给大人物的
This tower is dedicated to celebrities
zhè zuò tǎ shì zhuānmén gěi dà rénwù de
专门 can also serve as an adjective and mean "specialized".
Examples
学院开设有专门语言课程
The college has specialized language courses
xuéyuàn kāishè yǒu zhuānmén yǔyán kèchéng
他是手机方面的专门人才
He's an expert on mobile phones
tā shì shǒujī fāngmiàn de zhuānmén réncái