The Allen and Greenough is still under construction;
so some links may not work quite the way you would expect.
The Four Conjugations.
171. Verbs are classed in Four Regular Conjugations,
distinguished by the stem-vowel which appears before -re in the Present Infinitive Active: -
| CONJUGATION || INFINITIVE ENDING ||
| First || -áre (amáre)
|| á |
|| -ére (monére)
|| é |
|| -ere (regere) ||
| Fourth ||
|| í |