I want to know the answer to the following question:
What did the Pecheneg frequesntly do over the span of two centuries?
All the background I'm provided with is that "For over two centuries they launched sporadic raids into the lands of Rus′, which sometimes escalated into full-scale wars (such as the 920 war on the Pechenegs by Igor of Kiev reported in the Primary Chronicle), but there were also temporary military alliances (e.g. the 943 Byzantine campaign by Igor).". Is that enough to answer the question?
Answer: yes