To use Read&Write tools on Safari, you will need to enable the Read&Write extensions. There is a Screen Steps article for enabling the extensions.
2. Double Click the word of your preference for a definition in a word document.
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3. Select the "Dictionary" icon in the Read&Write tool bar.
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To View and Listen to a Video Tutorial:
Select the links below to watch and/or listen to the tutorial:
Dictionary and Picture Dictionary
How to Video for Using Read&Write Dictionary on a Mac (00:01:00)
Select the link below for a Screen Steps for how to enable Safari Extensions:
How to enable Safari extensions
How to Enable Safari Extensions (Mac)