The arguer may be right about…, but he eem to neglect to mention the fact that…
Contrary to generally accepted view, I argue that…
It i true that…, but thi i not to ay that…
The main/obviou problem with thi argument i that it i blind to the baic fact that…
It would be natural/reaonable to think that…, but it would be aburd to claim that…
There i abolutely no reaon for u to believe that…
At firt thought, it may eem an attractive idea, but on econd thought, we find that…
The problem/fact i that…
A far a I am concerned, I believe that…
Thoe who object to…argue that…But people who favor…, on the other hand, argue that…