Array in Swift returning error

I am trying to create a variable that gets a random word from an array. I am using the method below to find it however it give me an error "Missing return function expected to return 'String"

let array: [String] = ["Example1", "Example2"]

var chooseOne: String {

        [Int(arc4random_uniform(UInt32(self.array.count)))]

    }

How do I get the function to work? I am brand new to swift, and any help would be appreciated. Thanks in advance!