 <p>The below coding is also useful to perform only string value.By using variable to access the property list of abject after that by using it check the value is a NotANumber by using isNaN.The code given below is useful to you</p> <pre><code>var languages = { english: "Hello!", french: "Bonjour!", notALanguage: 4, spanish: "Hola!" }; // print hello in the 3 different languages for(a in languages) { if(isNaN(languages[a])) console.log(languages[a]); } </code></pre>