db.getCollection('products').update({
    "_id": ObjectId("5b13a6cd3085b36a286148b1"), 
    "classSubjects.id" : ObjectId("5cecd8b65d268603eb016ef3")
},

{
        $set: {"classSubjects.$" : {
            "id" : ObjectId("5cecd8b65d268603eb016ef3"),
            "name" : [ 
                {
                    "language" : "English",
                    "value" : "MySubject1 Changed"
                }
            ]
        }, }
}
)