If all the months of the year started with different letters, they could be called:
1. Anuary
2. Bruary
3. Cmarch
4. Dpril
5. Eay
6. Fune
7. Guly
8. Haugust
9. Iptember
10. Jctober
11. Knovember
12. LDecember
Note that these names are purely fictional and are not used in any official calendar system. The names of the months in the Gregorian calendar, which is the most widely used calendar system in the world, are derived from Latin and have been unchanged for centuries