How to Use the Feynman Technique to Master English Grammar

The Feynman technique is one of the most practical ways to learn anything, including English grammar. It’s simple: if you can’t explain a rule in plain language, you don’t fully understand it. No jargon, no memorising a textbook definition. Just you, a piece of paper, and a pretend student who knows nothing.

Grammar is perfect for this because many rules look easy but fall apart when you try to teach them. The technique forces you to find those cracks.

Why the Feynman Technique Works for Grammar

Most learners try to master grammar by reading rules and doing exercises. That gives you surface knowledge. But when you actually need to use the rule in conversation or writing, the logic disappears.

The Feynman technique flips that. Instead of memorising, you explain. The moment you stumble, you know exactly what you don’t know. No guessing, no wasted time.

Let’s walk through it with a real grammar point: the difference between present perfect and past simple.

Step 1: Pick One Rule and Write Down Everything You Know

Take a single grammar rule. Not “all tenses.” One at a time. For example: When do we use “I have seen” vs “I saw”?

Write a quick summary in your own words. Don’t check a book yet. Just put down what you think you know. It might look like this:

• Past simple: finished action in the past. “I saw that movie yesterday.”
• Present perfect: action that connects past to now. “I have seen that movie, so I don’t want to watch it again.”

Step 2: Teach It to a Five-Year-Old

Now pretend you’re explaining this to someone who doesn’t know what “tense” or “auxiliary verb” means. Use the simplest words you can.

Example: “When you did something at a specific time that’s over, use the shorter form. I ate lunch at noon. When the time isn’t important but the experience is still with you, use the longer form. I have eaten sushi before.”

If you use any grammar terms (like “past participle”), you’re not done yet. Simplify further.

Step 3: Find the Gaps

This is where the real learning happens. When you try to teach, something will feel off. Maybe you realise: “Wait, what about I’ve just finished work? That’s a specific time—‘just’—but we still use present perfect.”

Mark that. It’s a gap. Now go to a grammar resource and look up the rule for words like “just,” “already,” “yet.” Fill the gap.

Write a better, simpler version that includes that exception.

Step 4: Repeat Until Smooth

Keep revising your explanation until it flows without hesitation. You might need to re-simplify after adding new details. That’s fine. The goal is a clean, one-paragraph explanation you could give to a friend over coffee.

Here’s what a finished version looks like for present perfect vs past simple:

“Use past simple when the action has a finished time: yesterday, last week, at 3 PM. Use present perfect when the time is not specific or the action still matters now. For example: ‘I lost my keys yesterday’ (specific time). ‘I have lost my keys’ (I still can’t find them). Words like ‘just,’ ‘already,’ ‘yet’ usually go with present perfect because the action is connected to now.”

Now test it. Try explaining that to someone. If you get stuck, you know where to focus next.

A Real Example from My Own Learning

I used this technique when I kept mixing up “used to” and “would” for past habits. My first explanation was a mess. Then I taught it out loud to my dog (he’s a good listener). I realised I couldn’t explain when you can’t use “would” for a past state (e.g., “I used to have a blue car” – not “I would have a blue car”). That gap made me go back and learn the specific rule about states vs actions. Now I never confuse them.

Wrap Up: Make This a Habit

Apply the Feynman technique to one grammar rule each day. Spend 5 minutes explaining, 5 minutes filling gaps. Over a month, you’ll cover 30 rules in a way that sticks. No wasted revision, no memorising without understanding.

The best part? You don’t need a teacher or a fancy app. Just yourself and a willingness to sound silly while talking to an imaginary five-year-old.

Ready to see how your grammar really holds up? Take the free English level test on English Measure. It checks reading, listening, writing, and speaking – so you’ll know exactly where your gaps are. Start here: English Measure Test.