Work in groups of five
No links oK

a

explanation:

the correct answer is the first one.

sentence lenght varies according to word choice.you select which word to use and that will require to use other expressions that collocate with the word chosen.sentence length will vary   according to the choice of words you make to express your ideas.  

no. but, i heard its a good book. you could look up the answers or summary on some website.