Pulling those verses together:

I Walk The Line (or try to)
NP Nov 2011

I keep a close watch on the beer & wine.
I know the drinking limits that are mine.
"Should you be drinking?"
"Yes, I think I'm fine"
The copper (trooper) says "Please walk the line!"

I think my answers are so very true!
"Have you had many?"; "No, just one or two"
"Yes, at a stretch, it may have been a few!"
"I'm feeling fine"
"Just walk the line!"

As sure as night is dark, And day is light.
I keep that solid white line on my right. (US= I do all my driving on the right)
I keep my open bottle out of sight,
Yet still I find,
I walk the line.

To drink's a very very easy thing to do,
I'm sure I'm sober when the evenings through.
Though early on I may have 'called for Hugh'
Just one more time,
I'll walk the line.