I HAVE INSTALL AVAST HOME FREE FOR PAST 3 YEARS. I LIKE TO KNOW WHETHER I NEED TO INSTALL ANY FIREWALL LIKE ZONE LAB ALARM TO PROTECT MY PC FROM HIJACK. PLEASE GIVE AN ANSWER AS SOON AS POSSIBLE. TQ
Yes you should be running a firewall. Either turn on windows firewall (XP, Vista) or find a third party firewall such as Zone alarm or comodo.
BTW, welcome to the forums and Happy Holidays.
Yes, you need a firewall as avast is not a suite, it’s only an antivirus.
You can try ZA, Comodo or PCTools nowadays.
Oh, avoid CAPS (forum policy) 
Sory bec it my first time join this forum and thanks for information.
You’re welcome. Feel free to come back any time you need help or just to share experiences.