How do we know when to use block of 4 and when not to for inference questions in RC?
When two contradicting ideas are mentioned/stated in the passage ,for eg: Yesterday, she was happy → Today , she was _____ —> This means that we can use block of 4. So, we need three piece of information to predict the 4th piece Yesterday:happy :: Today : _____(sad) . In contrast, the inference question will mostly have two pieces of information that is directly stated in the passage and then you have to predict the other two.
Here is an additional video on tackling inference questions under the title : verbal for 160+ peeps