Em dash, en dash: How to put a long straight line between two words

How do you put a long straight line between two words ie longer than -

Do you mean to replace the space between words by a continuous line (called a leader line)? In this case, edit your question to tell how your words are spaced: standard space, optionally enlarged by justification, or resulting from a tab?

In the second case, various lines may be automatically substituted for the tab character.

.

  • Write -- and it will be substituted
    by (Auto Correct).
  • Insert special en or em dashes by
    inserting special characters (menu Insert or icon in standard bar)
  • Define a shortcut for any dash in
    Auto Correct function or Auto Text
    function
  • Write the U+hexadecimal value and hit ALT-X, for example U+2013 (en dash) or U+2014 (em dash); test with other character and only hit ALT-X anywhere in given text

From Em dash | The Punctuation Guide

Do not mistake the em dash (—) for the slightly narrower en dash (–) or the even narrower hyphen (-).

Be aware that your font contains characters like the above mentioned; there could also be some similar (minus sign, box drawings horizontal, horizontal bar)…

In Writer, you have the following predefined substitutions:

:-: → minus sign

:--: → en-dash

:---: → em-dash

All those autocorrect substitutions apply immediately as soon as you type the second colon. You can create your own “immediate substitutions” on Tools → AutoCorrect → AutoCorrect Options.