Having a solid argument/thesis is key to a high score. They want to see a clear point of view with examples that clearly support your claim. This is particularly true for the Issue task. Often you will be given a prompt like this:
Claim: In any field—business, politics, education, government—those in power should step down after five years.
Reason: The surest path to success for any enterprise is revitalization through new leadership.
You'll notice it's a pretty wide open prompt. This is both to your advantage and your challenge, as you'll have so much to choose from but little time to narrow it down. Pick your side quickly and start generating some examples that evidence your claim. My advice is to do a quick 2 min. brainstorm (you don't have much time for this after all). Something like:
Side: Disagree
Support:
- Not standard practice for many fields
- Cost of hiring & training new people is prohibitive
- Loss of skill, experience
- Loss of specialized skill sets that may be difficult to replace (e.g., niche surgeons)
- Too broad to apply to all fields
Generally, when you're in doubt, your best bet is to either agree or disagree and then support your claim. This is your simplest path to meeting their criteria and a higher score. BUT. You can get bonus points by being a little more complex:
Side: Time limits may be well-suited to some fields and professions, but not others.
Support:
- Time limits in some fields that keep the field revitalized, promote a balance of power, & ensure opportunities for younger generations (e.g., politics).
- In others, they would lead to loss of important skills that would be detrimental to society (e.g.., healthcare).
I'd go this route only if you've practiced and are feeling confident. It definitely makes organization more difficult.
In any case, addressing and arguing against a counterpoint will always land you a better score. Let's say I'm disagreeing with the above topic. I could write something like:
"Some argue that time limits ensure the revitalization of an enterprise. But for many businesses, the cost of training new employees to fit highly skilled roles in upper management is prohibitive. The damage done to the bottom line can prevent a business from expanding and thus stagnating - the opposite of vitality."
Following this format, I landed a 5.5 in my last GRE and have never scored below 5.0 (that 6.0 is elusive!). Highly recommend just sitting down and practicing. The more you practice, the easier this will come, and the more time you'll have to write a lengthy essay (which is also key).
Here is a list of common GRE prompts.
Good luck!!