Rule 8 refers to the phonogram 'wor'. There are five spellings for the sound er. They are ur (of nurse), ir (of first), ear and wor. The phonogram 'or' may say er when it follows wor.
For example:
Watch the tutorial video below to see how the Spelling Tools, Spelling Rule 8 and Reading Tools are used to spell challenging words.
Special Note:
Not all words will follow the spelling rule. These are called exceptions. If 90% or more words follow this rule then this is still a great tool to help become a proficient speller. Language experience will deal with the rest.