1. I eat cereal for breakfast.
2. I eat cereals for breakfast.
3. I eat cereal for my breakfast.
4. I eat cereals for my breakfast.
[Can we use all the expressions? Which expressions are common?]
1 and 3 are fine. The others aren’t.
Cereals is plural. Do you eat more than one at a time? Number 2 is not used. Number one is best. Numbers three and four are correct, but we would most commonly use number one.
The correct expression to use in this context is "I eat cereal for breakfast." This is the most common and natural way to convey that you eat cereal in the morning as your first meal of the day.
While all the other expressions are grammatically correct, they are less common and may sound a bit awkward or unnatural to native English speakers.
"I eat cereals for breakfast" could convey the same meaning as the correct expression, but it is not as commonly used. Typically, the singular form "cereal" is used to refer to the breakfast food as a whole.
"I eat cereal for my breakfast" and "I eat cereals for my breakfast" are technically correct, but they are less commonly used and may sound a bit redundant. The word "breakfast" already implies that it is your meal, so adding "my" is not necessary.
In summary, the most common and natural expression is "I eat cereal for breakfast."