- The effort to take western Mosul back from ISIS will be a battle of attrition
- Civilians trapped by the fighting have no easy escape route
(CNN)A familiar pattern is emerging as Iraqi forces begin the final phase of their offensive to clear ISIS fighters from western Mosul.
What does the battle look like?
What about the civilians?
Do the Iraqis have enough troops?
What comes next?
Will this be the end of ISIS in Iraq?
Since Mosul's capture by ISIS fighters in June 2014, Mosul has been a vital stronghold for ISIS.
The largest city under ISIS control in Iraq and Syria, it was the city from which the group first declared the establishment of its so-called caliphate.
Since then, ISIS has gradually lost its other Iraqi cities -- Ramadi, Tikrit and Falluja -- to government forces.
As many as 750,000 people are estimated to remain in Mosul, once a cosmopolitan trade hub of 2 million residents.