Verbs-come-second exceptions

I am trying to understand when small words & interjections at the start of a sentence get ignored with regard to the "verb comes second" rule.

In this sentence it gets ignored.  You say:
"Hey, du siehst ja nicht gerade sehr fröhlich aus!"
...instead of 
"Hey, siehst du ja nicht gerade sehr fröhlich aus!"

It works the same for:
"Nun, ich hatte vor einer Feuerwehrausfahrt geparkt."

But in this sentence the verb DOES come second:
"Na ja, kann man nichts machen."
…instead of 
“Na ja, man kann nichts machen.”

What is the difference?  Or can it go either way?  I understand how it works differently with coordinate vs subcordinate conjunctions, but these "little words" aren't conjunctions.

A somewhat related situation happens in this sentence:
"Spätestens am Flughafen würdest du dann aber doch geschnappt."

Here, following the TMP rule, I would've tried to put "am Flughafen" later in the sentence, perhaps:
"Spätestens würdest du dann aber doch am Flughafen geschnappt."

But I guess it's treating "Spätestens am Flughafen" as one phrase, so that it all comes before the verb.

Thanks.

Hallo RobertD50,

Thank you for your question! 

These little interjections (or exclamations or names) are often set off by a comma and don't count towards the "verb comes second" rule.

Here are some more examples:

“Ja, ich habe schon mein Zimmer aufgeräumt.” - “Yes, I have already tidied up my room.”

“Tim, dein Zimmer sieht sehr aufgeräumt aus.” - “Tim, your room looks very tidy.”

You can also think of the "verb comes second" rule as the verb being the second element, not always the second word which lines up with your last example above. Here are a few more examples:

“Der kleine Hund läuft dem Ball hinterher.” - “The small dog is running after the ball.” ("The small dog" is one element here)

“Schau mal, der kleine Hund läuft dem Ball hinterher!” - Look, the small dog is running after the ball!” 

“Wow, er läuft so schnell!” - “Wow, he's running so fast!"

Viele Grüße,

Julia

Thanks Julia, that makes sense.  But in this sentence they DO have the verb immediately following the interjection:

"Na ja, kann man nichts machen."
…instead of 
“Na ja, man kann nichts machen.”

Is there a reason for that?  Or is either version actually acceptable?

Hallo nochmal!

Yes, both versions are fine. There is a a slight difference in meaning though. 

“Kann man nichts machen.” is short for “Da kann man nichts machen.” and is a common colloquial expression meaning “It is what it is."  whereas “Man kann nichts machen.” means “There's nothing you can do.”

I hope this helps.

Grüße,

Julia

I see; thank you.