instruction: Is the next sentence syntactically and semantically acceptable?

Hank plays the guitar and finds arrangements for all the old folk songs which are still sung in these hills, and Ernie writes down all the old folk songs which are still sung in these hills.

response: acceptable

instruction: Is the next sentence syntactically and semantically acceptable?

Water pours easily onto the plants.

response: unacceptable

instruction: Is the next sentence syntactically and semantically acceptable?

They are special.

response: acceptable

instruction: Is the next sentence syntactically and semantically acceptable?

Bill followed the road into the forest.

response:
acceptable