How do i mark a question brainliest?

You have to have 2 answers on a question.  When you find a question that is pretty reasonable, you should see a little yellow crown.  

Explanation:

Practice on this if you need :D

Click on the little crown on the best answer.

Explanation:

I'm the 2nd answer so now you can finally give it to the other one :)

//Method declaration taking a parameter called myString of type String

public static boolean isEmailAddress (String myString){

//checking the @ character exists in string

if (myString.indexOf("@") != -1) {

  //checking if only one instance of @ exist in the string

   if (myString.indexOf("@") == myString.lastIndexOf("@")) {

   //checking if there's no space character

  if (myString.indexOf(" ") == -1) {

    //checking if there's no newline character in the string

    if (myString.indexOf("\n") == -1) {

      // checking if there's no tab character in the string

      if (myString.indexOf("\t") == -1) {

          return true;

      }

    }

  }

}

}

 return false;

}

Explanation:

The method takes in a string which is supposed to be an email address and checks if it is a valid email, it returns true if it is a valid email and returns false if not. the method checks the following conditions along the way.

->If "@" exists

->If there's only one "@" in the string

->If space character does not exists

->If newline character does not exists

->If tab character does not exist

it returns true if all the conditions are true.