go - What's wrong with this simple script?

Question

I study functions, wrote a simple script for the textbook, and there were 2 errors.

package main
import "fmt"

func zero(x int) {
    x = 0
    return x
}
func main() {
    x := 5
    x = zero(x)
    fmt.Println(x)
}

too many arguments to return (string return x)

How is "too many"? It's only one!

zero(x) used as value (string x = zero(x))

I don't understand what he says to me.

Answer 1

Waitting for answers