i am stuck i am getting this massage "Unexpected Identifier" what is wrong with my code

class Student {
  constructor(gpa, credits){
        this.gpa = gpa;
        this.credits = credits;
            }

           stringGPA() {
             return this.gpa.toString();
               }
                   get level(){

              if(this.credits>=90){
         return "they are a 'Senior' "
                           }
           else if(this.credit>=61){
     return they are a Junior
                             }
          else if(this.credits>=31){
       return "they are a 'Sophomore'"
           }
     else{
       return "they are a 'Freshman'"
     }

   }
}

const student = new Student(3.9);