Is this correct, 'Turn right when you see a shop with a blue advertisement'?
I mean there is a blue advertisement on the shop. If you see the shop, turn right.

Thanks!

Question

Is this correct, 'Turn right when you see a shop with a blue advertisement'?
I mean there is a blue advertisement on the shop. If you see the shop, turn right.

Thanks!

Answer

I would say,

There is a blue sign on the shop. When you see the shop, turn right.

Answer

'Turn right when you see a shop with a blue  signboard  ( Name of the shop, etc .
'Turn right when you see a shop with a blue advertisement sign ( inside /outside or on its wall/glass panel)

Answer

Yes, this sentence is correct.  
I would change only one thing:
"Turn right when you see the shop with a blue advertisement."

Answer

green?

Answer

广告牌，billboard
turn right when you see a shop with a green billboard

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