Please look at the rules for word formation listed in the book. And try your best to think of more words that fit the rules. For example: + er bank→banker compose→composer think→thinker + or educate→educator edit→editor sail→sailor + ant assist→assistant serve→servant depend→dependant + ist art→artist chemistry→chemist science→scientist + ian music→musician history→historian technique→technician 【查看更多】
