You will need to use the important words from the questions for your answers. Where possible, you can also use synonyms to repeat the same words.
This is important for achieving a high score for lexical resource (vocabulary) that matters for 25% of the total marks. The examiner will not be impressed if you only use the same words again and again. You also need to know how to paraphrase by using the best sentence structures and synonyms. Write the right range of words. Strictly adhere to word limits in tasks, like 150 words in Task 1 and 250 words in Task 2.