Grimm’s law and Verner’s law
Symbols:
S = stop
F = fricative
V = voice (+ or -)
A = aspiration
Stages:
1. Voiced aspirated stops become voiced fricatives
| +S (A) +V | ex | -> | Gmc +F +V | ex | 
| bh | bhreg- | β | βreg- | |
| dh | dhwer- | š | šwer- | |
| gh | ghosti- | γ | γosti- | 
2. Voiceless stops become voiceless fricatives
| +S –V | ex | Gmc +F –V | ex | |
| p | pisk | f | ||
| t | ten gnti γosti- | θ | θen gnθi γosti- | |
| k | kerd | x [-> h] | xerd -> herd | 
Remember that a preceding /s/ blocks Grimm’s law.
3. Verner’s law voices a fricative, if
| +F –V | ex | +F +V | ex | |
| f | β | |||
| θ | gnθi | š | gnši | |
| x | γ | |||
| s | z [-> r] | cf was/were lose/forlorn | 
4. Voiced stops become voiceless stops
| +S +V | ex | +S +V | ex | |
| b | abel | p | apel [apple] | |
| d | ed herd | t | et [eat] hert [heart] | |
| g | gene gnši βreg | k | kene [kin] knši βrek | 
5. Voiced fricatives become voiced stops
| +F +V | ex | +S +V | ex | |
| β | βrek | b | brek [break] | |
| š | šwer knši | d | dwer [door] kndi [kind] | |
| γ | γosti | g | gosti [guest] |