How to Change the Spell Check Language in Yahoo! Mail

In Yahoo Mail, you may not have to fight the spelling checker's suggestions. You can choose not only from languages but also often dialects. Yahoo Mail can also take a look at a message you're composing and determine the language in which it is predominantly written.

You can pick the Yahoo Mail dictionary for each message you are writing in Yahoo Mail. You can also change the default language. Here's how.

These instructions apply to the new Yahoo Mail and may not be the same for the Classic version.

Change the Spelling Checker's Language in Yahoo Mail

To choose the language used for spell checks in Yahoo Mail for a message you're composing:

Start composing a message using rich-text formatting. A rich-text message will have extra formatting options at the bottom of the screen.
Right-click in the message window, and then go to Spelling and Grammar and click on Show Spelling and Grammar.
The menu under Automatic by Language lets you select a new language. Click the one you want.

Choose Automatic by Language to have Yahoo Mail pick the language used for checking spellings based on the one you use the most in the email you compose. If your email contains multiple languages, it will only use the one it selects.
If you change the language in this menu, that will be the default language for all emails you write in the future.