What does the cryptic crossword clue "Test pulse regularly, for instance (7)" mean?

The definition is "instance". The wordplay uses alternating, charade. EXAM (synonym of "Test") + PLE (alternate letters of "pulse") [alternating: "regularly,"]; definition: "instance" The answer is Example.

Test pulse regularly, for instance (7)

Telegraph #29718 | 23 Across | 2021-07-03 flower

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