To understand any language, including Japanese, you need to know verbs — the words that convey action. Like English verbs, Japanese verbs have a few eccentricities, so you need to keep a few facts in mind when you're dealing with Japanese verbs:
Habitual actions and future actions use the same verb form, so taberu means I eat and I will eat. (You can think of it as the Japanese equivalent of present tense.)
You don't conjugate according to person. It doesn't matter who's eating — you use taberu for I eat, you eat, he/she/it eats, We eat, and they eat.
Use the stem form if you're adding a suffix to show politeness or another condition.
Use the te-form if you're adding another verb or an auxiliary verb to the main verb.
In Japanese, you don't conjugate verbs according to person; rather, you use different forms for present and past tenses, for affirmative and negative statements, for polite and informal speech, and to convey respect. The following table shows the various forms of taberu (to eat).