unit 1  wanting to find success!  practice  communication skills: introductions  grammar: tense (1)  reference answersunit 2  the pursuit of happiness  practice  communication skills: making requests  grammar. tense (2)  reference answersunit 3  the difference between plants and animals  practice  communication skills: invitation  grammar: tense (3)  reference answersunit 4  do animals think?  practice  communication skills: offering help  grammar: the singular or plural forms of predicates  reference answersunit 5  the energy crisis  practice  communication skills: suggestions  grammar: the consistency of subjects and  predicates (1)  reference answersunit 6  family  practice  communication skills: greetings  grammar: the consistency of subjects and  predicates (2)  reference answersunit 7  english meals  practice  communication skills: making apologies  grammar: adjectives  reference answersunit 8  how americans eat and drink  practice  communication skills: complaints  grammar: comparison (1)  reference answersunit 9  people and colors  practice  communication skills: approval and disaproval  grammar: comparison (2)  reference answersunit 10  better known as mark twain  practice  communication skills: making phone calls  grammar: infinitives  reference answersunit 11  money and finance  practice  communication skills: saying goodbye  grammar: gerund  reference answersunit 12  insurance  practice  communication skills: expressing thanks  grammar: participles  reference answersreferences