var arr=[{ email: 'abc@gmail.com', name: 'Abc' },
         { email: 'def@hotmail.com', name: 'Dr.Def' },
         { email: 'xyz@gmail.com', name: 'Xyz' },
         { email: 'cad@hotmail.com', name: 'Cad' }];

var arr=[{"email":"abc@gmail.com","name":"Abc"},
         {"email":"def@hotmail.com","name":"Dr.Def"},
         {"email":"xyz@gmail.com","name":"Xyz"},
         {"email":"cad@hotmail.com","name":"Cad"}];

var teacher = [];
for (let i = 0; i < arr.length; i++) {
        let fetchTeachers = JSON.stringify(arr[i]);
        teacher.push(fetchTeachers);
   }
console.log(teachers);

['{"email":"abc@gmail.com","name":"Abc"}',
 '{"email":"def@hotmail.com","name":"Dr.Def"}',
 '{"email":"xyz@gmail.com","name":"Xyz"}',
 '{"email":"cad@hotmail.com","name":"Cad"}']