had been adulterating
- past perfect progressive of adulterate.
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
The buying spree followed the melamine crisis when Chinese producers had been adulterating milk, baby formula and other foods with melamine, a chemical that is toxic in large quantities, to increase their apparent protein content.
From The Guardian • Feb. 23, 2020