You cannot talk about winning the war as long as there's killing and destruction on daily basis.
The army is making good advancement on daily basis against the terrorists. Of course, they still have the support of Turkey, Qatar, Saudi Arabia and some Western countries including the United States, but the only option that we have in that regard is to win.
"Winning" is a subjective word, but we are making advancement. This is the correct word, because winning for some people is when you finish completely.
We can say, you can win the war only when you restore stability in Syria.
If you don't win and the terrorists win, Syria wouldn't exist anymore.
Talking about winning and losing is like if you're talking about two armies fighting on two territories, which is not the case. Those [terrorists] are gangs, coming from abroad, infiltrate inhabited areas, kill the people, take their houses, and shoot at the army. The army cannot do the same, and the army doesn't exist everywhere.