Why do I like impromptu speaking?

4 types of speaking:
reading from manuscript
recite from the memory
extemporaneous speaking
impromptu speaking

1. spontaneous ideas （suitable）
daily life
personal feelings
daily words

2. fast to record (function)
save a lot of time
my diary moment
express myself genuinely and truly

3.organizing ability (practice)
have sth to say about a topic
a way to express and to talk
some ideas can surprise myself

All in all:
A record of my present life
A memory of my past life