The teachers in English Medium Schools usually teach their students in:

Concept: Approaches to teaching a language are classified by how the target language is presented and practised: the Direct Method uses only the target language for oral immersion in a dedicated language class; the Grammar-Translation Method teaches through translation and explicit grammar rules; the Bilingual Method alternates the mother tongue and the target language in a planned way; and the Structural Method introduces and drills the language’s core sentence patterns and grammatical structures in a graded sequence.

Application: In English Medium Schools, students must acquire sufficient command of English sentence structures to follow instruction across every subject, not only in a dedicated English-language class. Teacher-training material for this second-language-teaching context recommends the Structural Method precisely for this setting: it introduces and drills the graded sentence patterns and grammatical structures of English so that students build the structural competence needed across the whole curriculum — a broader goal than the single-classroom oral-immersion aim of the Direct Method.

Cross-check against each option:

• the direct method — a technique confined to a dedicated language class that uses only the target language with no translation — it describes a language-class technique, not the general school-wide medium of instruction.

• the grammar-translation method — relies on translating between the target language and the mother tongue, which is the opposite of teaching subjects directly in English.

• the bilingual method — deliberately alternates the mother tongue with the target language, which does not match instruction delivered directly in English.

• the structural method — builds the graded sentence-pattern competence in English that students need to access instruction across the curriculum, which is why English Medium School teachers commonly use it when teaching English to their students.

Result: The structural method is the correct answer, since it is the language-teaching method that builds the graded English sentence-pattern competence students need to access instruction across the curriculum, and it is accordingly the method English Medium School teachers commonly use when teaching English to their students.