we have to continue the study of the forecoming languages.

poor requirements if the requirements are unclear,incomplete
too general and not testable they will be problems

unrealistic schedule if too much of work of work is
scheduled in short time,problems are inevitable
inadequate testing no one know how test then it is going to
be a problem

request to pile feature when development is under way 

miscommunication if developers don't whats needed, customers
have erroneous expectations

Risk can come from any of the below:

1) People
2) Infrastructure
3) Hardware / Software
4) Technical Skills (Skill gap analysis)
5) Project Management
6) Logestics
etc..

Risk is any anticipated problem which can cause loss to the 
project (w.r.t S/W Industry) in terms of schedule & cost.