I was recently asked this question on my Facebook page:
‘I’d like to ask about including prepositions in writing answers to the Reading paper questions. For example, a question from GT reading test A from Cambridge IELTS 7, Q. #21 says:
‘Where do most employees collect their wages?’
The passage says:
‘Generally, employees pick up checks in their department; if not, they may be picked up at the Business Office.’
I answered ‘in their department’, but the answer in the book’s answer key was just ‘their department’. What do you think?
There are several important points to make here.
1) You MUST stick to the word limit you are given. I don’t have a copy of this book, so I don’t know the word limit that was given here. If the question says ‘no more than two words from the passage’ then the correct answer is ‘their department’. If the question says ‘no more than three words from the passage’ then ‘in their department’ would be allowed, but the word ‘in’ is not necessary. You must remember that these are practice tests and the answer key for the live tests is much more detailed – it is not possible to print exactly the same answer key in practice test books because it would be far too long.
2) The questions in the reading test focus on testing reading skills. So, if you are asked to write an answer in words, this is to show your understanding of the information in the passage – not your ability to create a grammatically correct phrase. Notice that the word ‘their’ in this answer is important in answering the question ‘where?’. It tells us which department we are talking about and so it is a necessary part of the answer. The preposition ‘in’ gives no extra information and that is why it is not necessary.
3) The aim of practice test books is to teach you the best way to answer questions in the test. For short answer questions like this, you do not have to include words like prepositions and you do not have to answer in a phrase. In fact, if the word limit is very short, it may well be incorrect to include these words. The book is trying to train you to only write the key content words that give the information you are asked for.