meter: intonation versus syllable count

You may have noticed, or you may have not, that the second line of the first verse in "Melanie" does not match the corresponding lines if it comes to the number of syllables. It's

if I caused you pain (5 syllables) versus

if your pleas were in vain (6 syllables),

if my words were too harsh,

if I hit you too hard

...

Does that matter? Not really. In the first line the intonation lies on the first word/syllable "if":

if I caused you pain

In the corresponding lines it lies on the second word/syllable, but the subsequent rhythm/meter is the same:

if your pleas were in vain

Thus, all that's required to achieve a good flow is adding an upbeat note before the next bar that begins with "your pleas" (let's assume a two-four-time bar that goes: stressed - unstressed | stressed - unstressed, an so on):

 -  if  |  your pleas |  were in  | vain

Have fun,

Bernd