There is nothing wrong with eating breakfast, it is grammatically correct.

There are three common ways to express eating and drinking in English, eat, take, have.

So how to use eat, take, have to express eating, the specific distinction is as follows:

1. eat is popular in the United States, it can refer to both "eat" and "drink", but when it is used as "drink", the word "drink" is used. "drink", but as "drink" speak usually used for "drink" soup and so on, such as: She is eating bread. Do you like to eat soup?

2. have is a common word for "eat, drink", but in the UK, have is often used instead of drink, and in the US, eat is often used instead of have. when used in conjunction with meal, dinne r, and other nouns for meals, have is used more often than any other word, e.g.: Han Mei usually has lunch at home. Han Mei usually has lunch at home. She wants to have a cup of tea.

3. take as "eat, drink" is more rare than eat, and is mainly used for "taking medicine", such as: Will you take a cup of tea? Take this medicine after each meal.

If you need to take a test and both of these expressions appear, then having breakfast is recommended.

Expanded:

To say "eat breakfast", use the verb have breakfast or eat breakfast? There are too many examples of have to mention. Here is an example of the verb eat:

Jane never eats breakfast. (Cambridge Advanced Learner's English Dictionary)

He had hunger pangs that went away after he ate breakfast. (Contemporary American Learner's Dictionary of English)

What he does makes him like a father or uncle.

With regard to this sentence, it is fine to say a father on its own, and a uncle on its own, but it is fine to say a father or uncle together. Such a phenomenon is very common in English. In addition to the example a short form of a word or expression (缩略语，缩写), which Mr. Chen cited, let's cite a few more examples from the dictionary. The following examples are taken from the Cambridge Higher English-Chinese Dictionary of Double Interpretation:

(1) An article of the Cambridge Higher English-Chinese Dictionary of Double Interpretation of act interprets it as: to behave or speak in?a false or artificial?way to put on an act; to put on airs; to put on a show

(2) The Cambridge Advanced Learner's English-Chinese Dictionary explains address as a verb as follows: to write?a name or address?on an envelope or parcel in (an envelope or parcel), or to write a name or address in (an envelope or parcel). or parcel 在(信封或包裹)上写上姓名（或地址）

(3)《剑桥高阶英汉双解词典》对使用动词的 adjudicate的一条释义为：to act as judge?in a competition or argument, or to make a formal decision about something to act as judge; judgment, ruling, decision

(4) Cambridge Advanced Learner's English-Chinese Dictionary explains adorable as a verb as follows: describes?a person or animal?that is easy to love because they are so attractive and often small and lovely. they are so attractive and often small lovely; pleasing

(5) The Cambridge Advanced Learner's English-Chinese Dictionary has a definition of adult as a verb: a person or animal that has grown to full size and strength. Adult; adult animal

It is more prudent to use separate articles, as in . . a father or an uncle / ...a word or an expression / ...a name or an address / a competition or an argument and so on. So if you are taking a test, it's best to use this kind of "caution".

English Q&A: Questions about eat breakfast and have breakfast