how can i block some ad blocks?

I selected ' Large Rectangle' ie 336* 280 in all my blog postings.

But in some pages ads appearing, only one link with big size( Large rectangle with one ad)
how can i avoid this type of ads?

 

You cannot avoid that, its automatic.

 

The large blocks usually displays 4 or 5 ads. However, sometimes you may get 1 or 2. Its a bit random, but on the whole, you will get either 4 or 5 ads.

 

It happens sometimes. No need to worry.

 

You cannot avoid that, its automatic.

 

yes, we can not manage it....it is automatic.