资源资源简介：

Unit  16
 The United States of America
(Word study and Grammar)
Revision of word formation
Noun formation
drive                 driver                      amaze                        amazement
fasten      -er          fastener             develop      -ment      development
open                  opener                     pay                            payment
teach                 teacher                    retire                         retirement

admire                     admiration         happy                       happiness
examine    -ation     examination       kind          -ness        kindness
organize                  organization       dark                         darkness
Adjective formation
dirt                      dirty                    pain                           painful
hair       -y           hairy                    hope        -ful            hopeful
smell                   smelly                  care                           careful

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