The Indo-European languages have a free stress, that is any syllable of the word can be stressed. In Germanic languages the stress became limited to the beginning of the word, usually the 1-st syllable is stressed.
OE /bringan
/Englisc
The fixation of the stress on the 1-st syllable had far reaching effects.
1) It caused the reduction of unstressed vowels in final position;
2) Final consonants were changed too.
These changes in phonetic structure greatly contributed to the changes in
morphology.
The 1-st or Germanic consonant shift is a specific feature of Germanic languages. In Germanic languages all Indo-European stop consonants change their way of articulation. The changes (they have three acts) are as follows:
Indo-European *p *t *k - *b *d *g - *bh *dh *gh
Germ. *f *Ø *h - *p *t *k - *b *d *g
The corresponding changes were summarized by J. Grimm, an outstanding philologist. And the whole complex of these changes is called Grimm’s Law.
*(this sign shows that the sounds are reconstructed).
a) Indo-European voiceless stops p, t, k became voiceless fricatives in Germanic f, þ, h.
Examples:
Indo-EuropeanGermanic
p > f Lat. piscus Goth. fisks – ON fiskr – OE fisc
Russ. полный Engl. full
t > þLat. tres Goth. þrei – OE þrēo
k > h Lat. octo Goth. ahtau – OE eahta
b) Indo-European voiced stopsb, d, g became voiceless in Germanic p, t, k.
b > p Lat. dubus – Goth. diups – OE dēop
d > tLat. duo – Goth. twag – OE twegen
g > k Lat. genu – OE kneo
c) The Indo-European voiced aspirated stops lost their aspiration in Germanic languages.