Listen to the sentences and complete them with the correct word or words (there will be between 1 and 4 missing).
Spelling is important both in the OET and in your working lives, and this exercise will help you to improve.

The molecular structure of the protein was determined using X-ray crystallography.
The researcher will source additional data for the study.
The radiologist will contrast the images to identify any abnormalities.
Early screening can detect cancerous cells before they spread.
The patient’s condition is complex and requires a multidisciplinary approach.
Only a fraction of patients experience severe side effects from the medication.
The organ donor saved several lives through organ transplantation.
The ELISA assay detected the presence of HIV antibodies in the patient’s blood.
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