MyPresentation can automatically check your texts in English and Russian for spelling and grammatical errors.
Words with spelling errors or that are absent from the dictionary are underlined with a red wavy line. Sentences with grammatical errors are underlined with a blue wavy line.
By default, spell check is enabled and grammar check is disabled.
To disable or enable spell checking, click the
button and run the Settings command from the main menu. In the Settings pane, in the Spelling and grammar block, clear or select the Check spelling or Check grammar checkbox.

When working in macOS, in the Tools > Spelling and grammar command menu, clear or select the Check spelling checkbox.
Enabling and disabling spelling and grammar checks applies only to the current document and does not affect other open documents.