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“Choose Edit > Spelling > Dictionary.
In the Language menu, choose a language. Each language contains at least one dictionary.
In the Target menu, choose the dictionary where you want to store the word. The Target menu lets you store the changes in an external user dictionary or in any open document.
In the Dictionary List menu, choose Added Words.
Click Hyphenate to see the words default hyphenation. Tildes (~) indicate possible hyphenation points.
In the Word box, type or edit the word to be added to the word list.
If you dont like the hyphenation points, follow these guidelines to indicate your preferred hyphenation of the word:
Type one tilde (~) to indicate the best possible hyphenation points, or the only acceptable hyphenation point, in the word.
Type two tildes (~~) to indicate your second choice.
Type three tildes (~~~) to indicate a poor but acceptable hyphenation point.
If you want the word never to be hyphenated, type a tilde before its first letter.”