Sentence three is the correct sentence. All of the others have some grammatical error in them. In the first, "felled" is incorrect and not a word. It also says "walk boots" instead of the correct verbal adjective "walking boots." In the second, "weren't" is not usually considered very academic and "tight" should be in the adverb form "tightly." Number four is wrong because it used "walked boots" instead of of "walking boots" and "tight" instead of "tightly." "Fallen" is incorrect in number 4, because it should have been "had fallen" if one was going to use the verb "fallen."
Can you please explain your question better?
Answer:
but much research has been done and more has learned about brain injuries in the last 5 years
Explanation:
because this shows they are telling more players about the injuries and informing them about the dangers of playing
A discourse community can be described as a group of people that share common goals, sources of information, terminology, and methods of communication along with a certain level of expertise and knowledge on a subject. However, it is often distinguished from 'speech community' on the grounds that speech communities are sociolinguistic groupings with communicative needs such as socialisation and group solidarity, whereas discourse communities are groupings based on common interests.
