How to deal with verbal part if one cannot finish all 30 questions in time?

[KW&BT]

Hello everyone,

I have a question on the strategy to deal with the verbal part if one cannot finish all 30 questions within 30 minute-period. What is the best strategy for this? For example, if I can do only about 20 questions within this 30 minutes, I have to do (1) all from the 1st to 20th questions and guess the others, or I do only for the first 15 questions and then balance 5 questions to all the left ones, or any other ways.

Also, do you have any recommendation to boost the ability to deal with SC and RC, instead of practicing only?

Thanks in advance.