Use Round brackets...ie(), when the Type annotation is used for an argument

scala> //#m:74

scala> val data = List(1, 2, 3, 4)
data: List[Int] = List(1, 2, 3, 4)

scala> data.foreach(x => println(s"This is ${x}"))
This is 1
This is 2
This is 3
This is 4

scala> //This do not work, as we have to wrap x:Int with Round Brackets

scala> data.foreach(x:Int => println(s"This is ${x}"))
:1: error: ')' expected but '(' found.
       data.foreach(x:Int => println(s"This is ${x}"))
                                    ^
:1: error: ';' expected but ')' found.
       data.foreach(x:Int => println(s"This is ${x}"))
                                                     ^

scala> //When the type of argument is explicitly specified(as here x:Int),

scala> //use Round brackets...ie()

scala> data.foreach((x:Int) => println(s"This is ${x}"))
This is 1
This is 2
This is 3
This is 4