Defining the Undefinable

Relative clauses, gerunds as subjects, and the vocabulary of big ideas

Quick Chat

Speak
What is "happiness"? Try to explain it without using the word "happy."

Hard, isn't it? Abstract concepts — things like freedom, success, trust — don't have a simple definition. Everyone understands them differently. That's what makes them great conversation topics, but you need specific grammar tools to talk about them.

Speak
What's the difference between how a 10-year-old would define "success" and how a 50-year-old would? Why does the definition change?

Today: the grammar structures that let you define, describe, and discuss ideas you can't touch or see.

Talking About Ideas

Abstract concepts need special grammar. Here are the three key tools:

1. Relative Clauses for Defining

"Freedom is something that means different things to different people."

"Courage is the thing that makes you act when you're afraid."

"It's a feeling which is hard to describe but easy to recognise."

"Something that..." / "a feeling which..." / "the thing that..." — relative clauses turn vague ideas into clear explanations.

"That" or "which" — does it matter?

In defining relative clauses (where you say WHAT something is), "that" and "which" are usually interchangeable.

"Success is something that looks different for everyone." = "Success is something which looks different for everyone."

In spoken English, "that" is more natural. In writing, "which" can sound more formal.

2. Gerunds as Subjects

"Being free means making your own choices."

"Having courage doesn't mean not feeling afraid."

"Achieving success requires knowing what matters to you."

Gerund (-ing form) at the start of a sentence = the action IS the subject. This lets you describe what abstract ideas involve in practice.

3. "It's about..." / "It involves..." / "It means..."

"Freedom is about being able to choose." / "Trust involves believing in someone."

"Success means different things at different stages of life."

These phrases connect the abstract word to a concrete explanation. "About" = the core idea. "Involves" = what it includes. "Means" = how to understand it.

4. Personal vs General

General: "Happiness is a state of mind." / "People often define success as..."

Personal: "For me, happiness is..." / "I'd describe courage as..."

B1+ speakers can switch between personal and general perspectives. This shows intellectual maturity.

Try it
Define "friendship" using all 4 tools: one relative clause ("something that..."), one gerund subject ("Being a good friend means..."), one "it's about/involves", and one personal view ("For me...").

Word Power

Tap to reveal. These are the abstract concepts you need to be able to discuss.

Abstract Nouns

freedom
the state of being free — "Freedom means different things in different cultures"
success
achieving your goals — "Success isn't just about money"
courage
acting despite fear — "Courage is something that grows with practice"
integrity
being honest and consistent — "Integrity is doing the right thing when nobody is watching"
ambition
strong desire to achieve — "Ambition can be positive or negative"

Defining Phrases

something that
relative clause starter — "It's something that everyone wants but defines differently"
a kind of
category/type — "It's a kind of inner strength"
the opposite of
contrast — "Courage is the opposite of giving up"
closely linked to
connected — "Trust is closely linked to honesty"
goes hand in hand with
always together — "Freedom goes hand in hand with responsibility"

Thinking & Reflecting Verbs

associate... with
connect in your mind — "I associate success with hard work"
define... as
give meaning — "I'd define happiness as feeling content"
distinguish between
see the difference — "It's hard to distinguish between ambition and greed"
relate to
connect with personally — "I can really relate to that idea of freedom"
comes down to
the core/essential thing — "In the end, happiness comes down to relationships"
Challenge
Close all cards. Pick any abstract noun and define it using: one defining phrase, one thinking verb, and one gerund sentence. All from memory.

The Definition Game

You have 90 seconds to define each concept. Use relative clauses, gerunds, and personal views. The goal: make your listener truly understand what you mean.

1:30
Round 1
Define "trust" — What is it? How do you build it? How do you lose it?

Start with a general definition, then give a personal example, then explain what destroys it.

Must use: "something that..." + "it involves..." + "for me..."

Round 2
Define "personal growth" — Is it the same as success? How do you measure it?

Compare it with success. Explain what it involves. Give a personal example of growth.

Must use: a gerund subject + "it's about..." + "closely linked to..."

Round 3
Define "respect" — Who deserves it? Should you earn it or give it automatically?

This has two sides. Define it, then discuss whether it should be earned or given freely.

Must use: "I'd define it as..." + "the opposite of..." + "comes down to..."

Round 4 — The Big One (2 minutes)
Define "a good life" — What makes a life good? Is it the same for everyone?

This is wide open. Define what "good" means, discuss different perspectives, and give your own view.

Must use: at least 5 different phrases from today's lesson + connect at least 2 abstract nouns together

Recall Zone

From CT-25: Talking About Progress
How do you talk about something you've achieved using the present perfect?

"I've learned..." / "I've improved..." / "I've become more confident at..."

When defining abstract ideas, personal experience matters: "I've learned that success isn't about money."

From CT-24: Checking You Understand
How do you politely ask someone to explain what they mean by a word?

"What do you mean by...?" / "Could you explain what you mean?" / "Could you elaborate on that?"

Abstract concepts often need clarification: "What do you mean by 'freedom' in this context?"

From CT-23: Building an Argument
What phrases show the other side of an argument?

"However..." / "On the other hand..." / "Having said that..." / "Although..."

When defining abstract concepts, balance matters: "For me, ambition is positive. However, some people see it as selfish."

What did you learn?

Final challenge
Pick any abstract concept NOT from today's lesson (e.g., justice, loyalty, creativity, wisdom). Define it for 90 seconds using at least: one relative clause, one gerund subject, and one personal view.

Which abstract concept was hardest to define today? Why do you think some ideas are harder to put into words than others?

← CT-25