How do I force it to use English for spelling?

[Mythobeast]

I’m trying to spell-check my document. It’s all in English, but for some reason it keeps identifying various words as mis-spelled French, Dutch, or one of several other languages.

Is there a way I can tell it to just spellcheck everything in English?

[Zizi64]

You can set the language property in the applied styles. Use the paragraph styles and the character styles in your documents.

[Wanderer]

@Mythobeast

just spellcheck everything in English?

No, the software is prepared to handle text in several languages. All you can do is setting your defaults right and to remember - as @Zizi64 already described - to keep an eye on your styles.

[mikekaganski]

Several things in play here:

1. How your text is attributed: i.e., which language is assigned to different parts of the document.

• this may come from:
  • styles;
  • system input (i.e., how you configured your keyboard layout / input language bindings on OS level; and considering this in LO is configurable using Options → Language Settings → Languages, Ignore system input language checkbox);
  • copy-paste from other sources (where the language attribution could already be present, or where paste dialogs can provide you respective choice)…

2. Installed spell checkers and dictionaries (i.e., if you do not have Hunspell/Myspell, or do not have a dictionary for a specific language used in your document, respective parts would not be spell-checked).
3. Installed grammar checkers (aka proofreaders): these include Lightproof with respective languages, and LanguageTool, which may be an extension, or - in recent versions - be built in, as a web service.

When you take care of point 1, and have points 2 and 3 set up to provide you the wanted English modules, you will be fine. When your text accidentally contains pieces in other languages, points 2 and 3 will define if those parts will be checked according to those languages, or simply excluded from check.

So:

@Mythobeast

Is there a way I can tell it to just spellcheck everything in English?

Yes there are ways. One is using Tools → Language → For All Text; notice that it will only convert all of your existing text to the chosen language, not prevent other languages from appearing in the future, when you will tell LibreOffice to do so (again, see point 1).

[Villeroy]

menu:Tools>Options>LanguageSettings>Languages>Default language for documents
Western: English(Autralia, UK, USA, whatever)
Check “For the current document only” if you want to change the setting for a loaded document or template. If you do not check this option, the setting applies to new documents that are NOT derived from any template.