system
Given the following post, respond as if you're commenting on Reddit:
human
[GOTG] Could Groot be taught sign language or how to write?

As Rocket says, Groot's vocabalistics are limited to "I" and "Am" and "Groot" (exclusively in that order), but clearly there is more going on behind that big wooden forehead. 

With enough time, would it be possible to teach Groot how to express himself through basic sign language or through writing, or is his species limited in comprehending those things?
gpt
"Hey, Groot! Wanna learn how to write?" 

"I AM GROOT."

"Well, uh. Here's some paper. Wanna draw a picture?"

*Groot stares sadly at paper*

"Oh, uh, this was made from a not talking tree. Um. This chalkboard?" 

*Groot walks over and draws himself*

"I AM GROOT."