How do I use variables in single quoted strings?

Question

I am just wondering how I can echo a variable inside single quotes (I am using single quotes as the string has quotation marks in it).

     echo \'test text          


        

Answer 1

The most readable, functional way uses curly braces inside double quotes.

'test text "here_is_some_test_text_'"${counter}"'" "output"' >> "${FILE}"