Expression "good luck"

[Dongi]

English Grammar Tests, Elementary Level

ESL/EFL Test #29 "Responses (2)", question 9

Mike: 'I'm taking my driving test tomorrow.'
Jane: '.........'

(a) Good fortune.
(b) Good luck.
(c) Good outcome.
(d) Good success.

English Grammar Tests, Elementary Level

ESL/EFL Test #29 "Responses (2)", answer 9

Mike: 'I'm taking my driving test tomorrow.'
Jane: 'Good luck.'

Correct answer: (b) Good luck.

Your answer was: incorrect
Mike: 'I'm taking my driving test tomorrow.'
Jane: 'Good success.'
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I wonder why is not answer "Good success". Because I think good luck means is passive hope.
and good success means "I believe you'll past your exam".
Could you explain more for me, Thank you.

Dong

[Alan]

Hi Dong,

The usual expression when you want to express to someone your good wishes before an exam, for example is: Good luck. If you want to use the word success/successful, then you would say; I wish you every success or I hope you are successful.

Alan
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English as a Second Language
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