New Post: issues while using HTMLagility pack

I tried using HTMLagilitypack but the api seems to have get changed and many properties and functions under that api is not working.
for eg. string text = doc.DocumentNode.SelectSingleNode("/html[1]/body[1]/p[1]").InnerText;

The SelectSingleNode is not working because of which I am unable to get data from document.
Can somebody please provide me with the alternative to this?