Introduction
The aim of this work is to show how the combination of modal auxiliary verbs and passive voice is used in English language.

As examples of the language, I have decided to use two totally different sources of text. The first one, Thomas Harris’s Hannibal, is a thriller fiction for adult readers. The book uses American English. The second book, J. K. Rowling’s Harry Potter and the Goblet of Fire, uses British English and its readers are mainly children, so in my opinion, the language should be simpler to be understood. On the other hand, American English is known for its tendency towards simplicity of the language. It would be interesting to see the contrasts (if any) between these two books. Both books consist of approximately five hundred pages what gives adequate amount of material to be analysed.

Naturally, I would not only be dealing with the differences between British and American English, or between adult and children literature, but my field of study will also include reasons why passive voice was used instead of active, what is its connection with modal verbs and in what structures do they co-occur.

The research findings should also correspond with the theory of the grammatical background, but the known fact is that pragmatic English does not always agree with theoretical English. If any differences are found, they will be mentioned in the conclusion.

To boot, this seminar work should help teacher explain modal verb and passive voice connections that appear in everyday language, as well as give more examples of such structures in case the instances are insufficient when teaching this topic.

Grammatical background to modal verbs and passive voice
Modal auxiliary verbs

Definition
Firstly, we should define what modal auxiliaries are and what is their function. Modals are auxiliary verbs that function not only grammatically, but they also carry some additional meaning that they add to a lexical verb. This supplementary meaning usually expresses speaker’s attitude towards reality.

Division
Four groups of modals are distinguished:

1.central modals
We recognize nine central modal auxiliary verbs that express modality: can, could, may, might, shall, should, will, would and must. These central modals are finite, do not have -s form when a noun is in the third person singular and always have to be followed by bare infinitive or verb phrase as they do not carry full lexical meaning. They all have three forms: nonnegative, uncontracted negative and contracted negative. However, contracted negative forms of may (mayn’t) and shall (shan’t) are relatively rare and even nonexistent in American English. In addition, Biber (1999, 485) groups modal according to the time they refer to, thus he distinguishes between modals that refer to non-past time (can, may, shall, will) and modals that can refer to past time (could, might, should, would).