<?xml version="1.0"?>
<!DOCTYPE BATCH SYSTEM "exercises_oup.dtd"><batch>
<exercise subhead="dragdrop"/>
<media type="none"/><head><title>Sentence Match</title><task>Type in the word missing from the sentences.</task></head>
<body findword="substance">
<item><text>Even innocuous _________s can sometimes register a positive result in a drug test.</text></item>
<item><text>a natural _________ found in the body of animals</text></item>
<item><text>foreign _________s that contaminated the experiments</text></item>
<item><text>a bag full of some unknown _________</text></item>
<item><text>the material _________ of which we are made</text></item>
</body>
</batch>

