title: Primary constructor call expected
body: <p>this is example of inheritance in Kotlin.</p>
  <pre><code>open class Person() {
      var _name : String = &quot;&quot;
      var _age : Int = 0
  
      constructor(name: String, age : Int)  : this(){
          _name = name
          _age = age
      }
  }
  
  class Student() : Person() {
      var _university : String = &quot;&quot;
  
      constructor (name : String, age: Int, university: String) : super(name, age){
          _university = university
      } 
  }
  
  fun main() {
     var person = Person(&quot;a&quot;, 10)
     var student = Student(&quot;b&quot;, 18, &quot;MIT&quot;)
     println(&quot;${person._name} : ${person._age}&quot;)
     println(&quot;${student._university}&quot;)
  }
  </code></pre>
  <p>How can I resolve error &quot;Primary constructor call expected&quot; in this case?</p>