Can I use "朋“ instead of "朋友”?
Hello, I'm studying chinese these days..here is a trouble

I know in 现代汉语，We all use 朋友 instead of 朋
(maybe in 古代汉语, It can be used alone)
every dictionary says 朋 means friend..but we do not use it alone these days(maybe?..I'm not sure..)

What I want to know is..when I first see a LETTER (for example, 怒)
How can I know it can be used ALONE?
看到这个场面，他非常怒 - Can I Say this in 现代汉语?

Question

Can I use "朋“ instead of "朋友”?
Hello, I'm studying chinese these days..here is a trouble

I know in 现代汉语，We all use 朋友 instead of 朋
(maybe in 古代汉语, It can be used alone)
every dictionary says 朋 means friend..but we do not use it alone these days(maybe?..I'm not sure..)

What I want to know is..when I first see a LETTER (for example, 怒)
How can I know it can be used ALONE? 
看到这个场 面，他非常怒 -> Can I Say this in 现代汉语?

Answer

You can't use these words alone in morden chinese. We usually use words in pair to express more detail， like 怒， we got幩怒、惱怒...etc

Answer

We normally use 朋友in our conversation/writing, 朋somehow sounds weird

Instead of 非常怒，非常愤怒sounds better

Answer

朋 means are classmates that you had become friends with in ancient times when boys go to study in a private setting under a common teacher.  Anyone else you know from elsewhere is known as 友.  I am sure if you watch Korean drama serials, you may see this sort of thing.  So together, 朋友 has become a generic term for "friends" from all walks of life.

So if you see a phrase such as 远朋近友, you will know exactly what it means.  It has a deeper meaning than just the translation of "Friends from far and near"

Answer

Most words in modern Chinese consist of two characters. In some cases, we use 朋 and 友 to represent 朋友. Example: 远朋：远方的朋友， 旧友：相识多年的朋友. BTW, 朋 has multiple meanings in ancient Chinese, not necessarily means friends.

Answer

I don't think that kind of dictionary exists [emoji][emoji]
I think it is by experience, if you listen more you'll know whether a letter alone sound smooth(not weird) in a conversation