To pass away is to die.
Examples of use:
1. Alice’s aunt has passed away.
2. The vet has told Carl that his dog is very ill and it will pass away soon.
3. JD Salinger, the author of the Catcher in the Rye, passed away this week.
infinitive – pass away
present simple – pass away and passes away
-ing form – passing away
past simple – passed away
past participle – passed away
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