The basic verb in Russian that means “to eat” is есть/съесть. Notice that the second letter of the perfective forms is a hard sign, not a soft sign. This is one of the four most irregular verb stems in the language. (The others are the stems of дать, хотеть and бежать.)
|No such thing as
There are a couple potentially confusing points here. Notice first of all that the imperfective infinitive is spelled the same as есть, that quirky present tense form of “to be” that appears in “there is/are” and “have” sentences.
The next trick is that есть is actually pronounced differently from ест. In both words the first sound is a y sound as in yes, but the vowel quality is different:
|есть||In this word the с and the т are soft, and the е is pronounced as a closed vowel, which means it almost sounds like the a in fate.|
|ест||In this word the с and the т are hard, and the е is pronounced as a lax vowel, which means it almost sounds like the e in yes.|
Here are a couple sentences where you can hear the difference:
|У тебя есть братья?
Do you have any brothers?
|Оля не ест мясо.
Olya doesn't eat meat.
As to the grammar of the verb, the thing that you eat shows up in the accusative case:
|Ты уже съел батончик шоколада?||Did you already finish eating that chocolate bar?|
|Когда я ем мясо, у меня болит живот.||When I eat meat, my stomach feels bad.|
|Когда мы были в Африке, мы ели кузнечиков.||When we were in Africa, we ate grasshoppers.|
|Иоанн же носил одежду из верблюжьего волоса и пояс кожаный на чреслах своих, и ел акриды и дикий мёд.* (source)||And John wore clothing of camel hair and a leather belt on his loins, and he ate locusts and wild honey.|
In English we often say things like “I ate breakfast/lunch/dinner,” and in Russian theoretically it's grammatical to say things like «Я (съ)ел завтрак/обед/ужин.» But frankly the Russians rarely say that. Instead they subsitute the verbs that directly address those meals: «Мы (по)завтракалали/(по)обедали/(по)ужинали».
* The careful student may notice that in this sentence the accusative plural акриды copies the nominative plural, which is atypical for modern Russian. Animate accusative plurals did not always automatically copy the genitive. This change began hundreds of years ago with words referring to male human beings, and then it eventually spread to other noun classes. That process is nearly complete in modern Russian, although there are still a few constructions where animate nouns sometimes occur in the accusative plural in a form that copies the nominative.
One of the words that means 'to eat' is кушать. Theoretically one can say мы кушали пиццу 'we ate pizza.' But this word is not one that usually comes from the lips of a grown man. It's a word used by Mama and Gramma when calling people to the table by saying идите кушать, or they might ask if you want to eat by saying вы кушать будете? But even when Mama and Gramma say it there is something domestic, affectionate or cuteish about it.
There is also an old fashioned language rule that says you should never use the verb кушать in the first person.
If you want to ask if someone wants to eat, the most neutral way is to say Будешь есть/завтракать/обедать/ужинать? Cruder versions are Будешь жрать? Будешь хавать? (The хавать version is a Belarusian influence.)