what does 'have a change of heart' mean?

[paradigma]

English Grammar Error, Intermediate level

ESL/EFL Test #11 "I really wonder", question 6

Although he had made every effort to show that he had had a change of heart and would try to go straight in the future, nobody was in the least convicted.

(a) every effort
(b) had had
(c) go straight
(d) convicted

English Grammar Error, Intermediate level

ESL/EFL Test #11 "I really wonder", answer 6

Although he had made every effort to show that he had had a change of heart and would try to go straight in the future, nobody was in the least convinced.

Correct entry: convinced
The error was: (d) convicted
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what does 'have a change of heart' mean ? thank you for your explanation. best regard

paradigma

[Mister Micawber]

.
change of heart = change of mind for emotional reasons
.
_________________
Canadian-American native speaker
who teaches English for a living at Mister Micawber's
ESL cafe: Interview with Mister Micawber