Exams that draw on this subject
If your paper is one of these, this subject is worth the hours.
Working on this subject
Concepts, then drills, then the clock
Read the explanations
Including on the questions you got right. The working transfers; the answer key does not.
Practise in your medium
English and हिन्दी are the same question behind a toggle, so progress carries across.
Then take it timed
Once the subject stops surprising you, mix it into a timed paper and see whether it still holds under a clock.