Don't use two hyphens (--) to make a dash; and don't use a hyphen for a minus sign.
And don't use a hyphen for a minus sign. Don't use two hyphens--to make a dash.
Don't use two hyphens--to make a dash. And don't use a hyphen for a minus sign.
Don't use two hyphens--to make a dash. And don't use a hyphen for a minus sign.