I, as an IELTS examiner, will certainly be looking for some fixed vocabulary phrases in your letter.
Some examples of fixed phrases are:–
- I hope that you will take action soon
- I look forward to your response
- Hope to catch up with you soon!
- Lots of love, Mary
- Best regards
- Yours faithfully or Yours sincerely
- Best wishes
- I am writing to….
- Hope I am not causing you too much inconvenience.
- I hope to hear from you soon
- Hope to catch up with you soon!
and more ….. more…..
If you can address these all, you are certain to be scored band 9 in terms of vocabulary or lexical resources.