- â\88\80G,L,T1,T. â\9dªG,Lâ\9d« ⊢ T1 ➡*[h,n1] T →
- â\88\80T2. â\9dªG,Lâ\9d« â\8a¢ T2 â\9e¡*[h,n2] T â\86\92 â\9dªG,Lâ\9d« ⊢ T1 ⬌*[h,n1,n2] T2.
+ â\88\80G,L,T1,T. â\9d¨G,Lâ\9d© ⊢ T1 ➡*[h,n1] T →
+ â\88\80T2. â\9d¨G,Lâ\9d© â\8a¢ T2 â\9e¡*[h,n2] T â\86\92 â\9d¨G,Lâ\9d© ⊢ T1 ⬌*[h,n1,n2] T2.