谁……呀？ who...?
   
     谁 can be used I a rhetorical question with 呀 at the end to emphasize a point-no answer is expected.
 
                             谁 + VP  +（呀）？
Examples:
1. 谁不知道中国发展快呀？
Who doesn't know China has been developing quickly?
2. 谁做生意不想赚钱呀？
Who doesn't want to earn money while doing business?

Substitutive drills: