A test of English language incorporates three important sections: Grammar, Vocabulary, and Comprehension which enable the examiner to understand the level of English understanding, speaking, writing, analysing and listening power. The skill to deconstruct unknown words from both the context and structure reveals a lot about your mental faculty and analytical abilities also. 

Scope and Importance

Grammar is what structures a language and makes written or oral content more comprehendible and interesting, thus laying the groundwork for effective communication. Grammatical errors come in all forms and they can easily confuse, obscure meanings and bring down the clarity of an intended message.  The usual errors are with sentence structure, tense of subject or verb, punctuation, spelling, and other basic mechanics and parts of speech.

Vocabulary plays a major role in a language like English where there are subtle differences in meaning even betwen synonymns. This underlines the importance of vocabulary to express ideas succinctly and effectively. A large vocabulary also correlates well with the capability to handle complex ideas.

Comprehension is an interactive process that goes beyond reading the text on the page as it involves finding meaning of the text, make inferences from the passage and be able to summarize, reiterate, and use critical thinking skills to answer questions related to the text. This will need good understanding of the first two aspects viz. vocabulary and grammar. Students with excellent comprehension skills are able to understand both the main idea and the details of any given text, and they are able to identify the different components of the text as well.