Have you ever wondered when to use who, whose, or whom?
You are not alone! These relative pronouns can be confusing because they look very similar, but each one has a different function in a sentence.
This simple visual guide with clear explanations will help you understand the differences.
The diagram also shows the connection between subject pronouns, possessive adjectives, and object pronouns, so you can better understand patterns like he → his → him or they → their → them.
Use this material as extra practice after class, while studying at home, or anytime you need a quick grammar review. The explanations are written especially for ESL students, with simple language and practical examples to make learning easier and less stressful.
In English, can, could, and would are very common modal verbs. We use them in everyday situations.
However, many learners feel confused because these words have different meanings.
The good news is that we can organize them into 3 different groups:
🟢 Ability
We use can and could to talk about ability, what a person is able to do. This can be something you can do now, or something you were able to do in the past.
🔵 Permission
We use can and could to talk about permission. For example, when we ask if something is OK, or when we give someone permission to do something. Could is more polite than can.
🟣 Polite Requests
We use can, could, and would to make requests. For example, when we ask someone to do something for us. Would is the most polite, and could is also polite.
Understanding how to connect ideas is an important part of speaking and writing in English. In this lesson, we look at two very useful structures: so/such… that and too… to / (not) enough… to. These help you explain reasons, results, and limits in a clear way.
1. SO / SUCH … THAT
We use so and such to talk about a cause, and that to show the result.
👉 Grammar
so + adjective + that
I’m so tired that I want to sleep right now.
such + a/an + adjective + noun + that
It was such a good movie that I watched it twice.
👉 When to use SO
Use so before an adjective or adverb. ✔ The people were so friendly that I felt relaxed.
👉 When to use SUCH
Use such before an adjective + noun. ✔ It’s such a beautiful day that I want to go outside.
Examples
The problem was so big that I needed help.
She has such long hair that everyone notices her.
2. TOO … TO / (NOT) ENOUGH … TO
These structures explain that something is more or less than we want or need.
👉 TOO … TO
Use too + adjective + to + verb → shows something is more than you want or a negative result.
✔ It’s too cold to go for a walk. ✔ He was too nervous to speak.
👉 (NOT) ENOUGH … TO
Use:
not enough + noun ✔ There isn’t enough time to finish.
adjective + enough ✔ She isn’t strong enough to lift it.
→ means you don’t have as much as you want.
Let’s Practice!
Practice 1
Practice 2
Practice 3
Speaking
Practice 1
Discuss the following questions
Practice 2
Read the information in the card.
Make a sentence using too, enough, so or such.
Example:
The card says: “There were 20 chairs and 20 people.”
My sentence: There were enough chairs to seat all the people .
Learning the passive voice help us focus on the action and the result, rather than on who performs the action. In many real-world situations. For example, in news, formal writing, academic reports, and instructions, the doer of the action is unknown, unimportant, or obvious. That’s where the passive becomes essential.
This lesson reviews the form and use of the passive in all main verb tenses included at B1 level.
1. Why We Use the Passive Voice
We use the passive when:
The doer is unknown: My wallet was stolen.
The doer is not important: These phones are made in Korea.
The result is more important than the person: The meeting has been cancelled.
The sentence sounds more formal or objective: The survey will be analysed next week.
Non-defining relative clauses help us add extra information about a person, place, or thing. This information is not essential to understand the sentence. The clause contains an additional, interesting detail.
👉 We always use commas with non-defining relative clauses. 👉 We NEVER use “that” in non-defining clauses.
What Is a Non-Defining Relative Clause?
A non-defining relative clause:
gives extra information
is separated with commas
uses relative pronouns like who, which, where, when, whose
can be removed and the sentence still makes sense
How to Form Non-Defining Relative Clauses
Non-defining relative clauses give extra information about a person, place, or thing. This information is not essential to understand the main idea. We always use commas to separate the extra information.
1. Structure
Main clause, relative pronoun + extra information, rest of the sentence.
2. Common Relative Pronouns (for Non-Defining Clauses)
Relative Pronoun
Used For
Example
who
people
My English teacher, who is from Canada, is very friendly.
which
things / animals
The book, which I finished yesterday, was fantastic.
where
places
Vancouver, where my cousins live, is beautiful.
when
times
2010, when I finished high school, was an important year for me.
whose
possession
Anna, whose car broke down, arrived late.
📝 Important:
Always add a comma before and after the clause (unless it ends the sentence).
Don’t use “that” in non-defining clauses.
3. Comma Rules
Put a comma before and after the non-defining relative clause (unless it’s at the end of the sentence; then you only need one comma).
4. Key Points for Low-Level Learners
You can remove the extra information and the sentence still makes sense.
The verb form inside the clause follows normal grammar rules.
Do not use these clauses to identify someone/something. (Those are defining clauses.)
Examples:
My brother, who lives in Mexico, is visiting next month. (extra info: he lives in Mexico)
The Eiffel Tower, which is in Paris, is very popular. (extra info: its location)
September, when the weather is mild, is my favorite month. (extra info: weather in September)
Chichén Itzá, where millions of tourists go each year, is amazing. (extra info: visitors)
🧠 Compare: Defining vs. Non-Defining
Type
Purpose
Example
Commas?
Use “that”?
Defining
Necessary information
The man who works here is kind. The man that works here is kind.
We use modal verbs like must, have to, need to, and their negatives to talk about things that are necessary or not necessary. For example, rules, duties, or responsibilities. We can also use them to talk about permission in the present or past.
🔹 1. Obligation in the Present
We use must, have to, and need to when something is necessary or important to do.
Structure
Example
Meaning
must + base verb
I must finish this project today.
Strong personal obligation
have to + base verb
I have to work on Saturday.
External rule or schedule
need to + base verb
You need to wear a helmet.
It’s necessary or required
🧠 Tip:
must = personal obligation (you feel it)
have to = external obligation (someone else decides it)
I must study more. (I want to) I have to study more. (My teacher said so)
🔹 2. NO Necessity in the Present
We use don’t have to or don’t need to when something is not necessary.
Structure
Example
Meaning
don’t have to + base verb
You don’t have to come if you’re busy.
It’s optional
don’t need to + base verb
She doesn’t need to wear a uniform.
It’s not required
🧠 Note: They mean the same, but don’t have to is more common in everyday English.
🔹 3. Prohibition (Something Is Not Allowed)
We use mustn’t (must not) to talk about rules or strong advice — when something is not allowed.
Structure
Example
Meaning
mustn’t + base verb
You mustn’t park here.
It’s forbidden
be not allowed to + base form
You are not allowed to park here.
No permission
🧠 Tip: ❌ Don’t confuse mustn’t (not allowed) with don’t have to (not necessary).
You mustn’t smoke here. → It’s against the rules. You don’t have to smoke. → It’s your choice.
🔹 4. Obligation and Necessity in the Past
We can’t use must for the past. Instead, we use had to or needed to.
Structure
Example
Meaning
had to + base verb
I had to finish my homework last night.
It was necessary in the past
needed to + base verb
We needed to buy tickets early.
It was necessary
For the negative, we use didn’t have to or didn’t need to (something was not necessary).
We didn’t have to go to school yesterday. She didn’t need to call — I was already there.
🔹 5. Permission (Present and Past)
We can use be allowed to or could to talk about permission.
Time
Structure
Example
Meaning
Present
am / is / are allowed to/can
Students are allowed to use phones at break. Students can use their phones at break.
