The language used in the questions
If the language used in questions in a reading test is harder to understand than the passage itself, the reader is presented with an additional difficulty, making it impossible to tell whether a candidate’s poor performance is caused by the difficulty of the text or the language in which the question is phrased. In IELTS reading tests, all instructions and questions are written explicitly and clearly, only 20% of the candidates (see Table 4) found it difficult to understand what the question requires them to do.