Mustn’t vs. Don’t have to – English Grammar Exercises for B1
Choose the best option (A, B, C, or D) to complete each sentence. Read the conversation carefully, as all questions are part of a relaxed Saturday morning chat between two roommates.
1 It is finally Saturday morning! I am so happy that we ______ wake up at 6 AM today.
(a) shouldn’t
(b) don’t have to
(c) haven’t to
(d) mustn’t
2 I turned off all my alarms last night because I ______ rush to the bus stop for my 8 AM class.
(a) mustn’t
(b) don’t must
(c) don’t have to
(d) can’t
3 The absolute best part of the weekend is that we ______ wear our uncomfortable work uniforms.
(a) aren’t have to
(b) shouldn’t
(c) mustn’t
(d) don’t have to
4 You can stay in bed all morning; you ______ get up until you are actually hungry for breakfast.
(a) don’t have to
(b) doesn’t have to
(c) mustn’t
(d) aren’t to
5 But remember our weekend roommate agreement: you ______ play loud music before 10 AM while I’m sleeping!
(a) mustn’t to
(b) don’t need
(c) mustn’t
(d) don’t have to
6 We bought plenty of groceries yesterday evening, so we ______ go to the crowded supermarket today.
(a) haven’t to
(b) couldn’t
(c) mustn’t
(d) don’t have to
7 My manager just sent an email, but since it is my day off, I ______ reply until Monday morning.
(a) don’t have to
(b) mustn’t
(c) don’t have
(d) shouldn’t
8 I might make some pancakes later, but you ______ help me cook if you’re feeling lazy.
(a) wouldn’t
(b) don’t have to
(c) mustn’t
(d) don’t have to helping
9 I am fine with you using my special coffee mug, but you absolutely ______ break it!
(a) don’t must
(b) mustn’t
(c) don’t have to
(d) haven’t
10 Since the apartment is already spotless, we ______ spend our relaxing Saturday doing chores.
(a) mustn’t
(b) aren’t need to
(c) don’t have to
(d) haven’t to spend
11 My boss is traveling right now, which means our team ______ submit the daily progress report today.
(a) doesn’t have to
(b) mustn’t
(c) don’t have to
(d) shouldn’t
12 You ______ eat breakfast with me if you want to keep sleeping. I really don’t mind eating alone.
(a) mustn’t
(b) not have to
(c) don’t have to
(d) won’t
13 We can watch a movie tonight, but we ______ choose right now. Let’s just decide later.
(a) don’t have to choosing
(b) don’t have to
(c) mustn’t
(d) aren’t supposed to
14 Just a quick warning: you ______ use the washing machine today because the motor is broken and it might flood.
(a) don’t have to
(b) mustn’t to
(c) mustn’t
(d) shouldn’t
15 The weather is terrible outside, but luckily we ______ leave the house for any reason today.
(a) don’t have to
(b) mustn’t
(c) haven’t to leave
(d) shouldn’t
16 My sister is visiting later, but she said we ______ pick her up from the train station. She prefers taking a taxi.
(a) couldn’t
(b) mustn’t
(c) don’t need
(d) don’t have to
17 You can borrow my laptop to watch Netflix in bed, but you ______ delete any of my university files!
(a) mustn’t
(b) don’t have to
(c) mustn’t deleting
(d) couldn’t
18 One of the greatest feelings in the world is knowing you ______ prepare a packed lunch for the office.
(a) didn’t have to
(b) mustn’t
(c) don’t have
(d) don’t have to
19 We can order a fresh pizza if you are hungry; you ______ eat the leftover salad from yesterday.
(a) haven’t to eat
(b) don’t have to
(c) mustn’t
(d) shouldn’t
20 The only strict rule this weekend is that we ______ talk about work or exams. Total relaxation is mandatory!
(a) don’t have to
(b) shouldn’t
(c) don’t must
(d) mustn’t
ANSWER KEY & EXPLANATIONS
1 (b) don’t have to
- Why it is correct: Waking up early is not an obligation today. You can wake up at 6 AM if you naturally do, but there is no pressure.
- Distractor Analysis: (d) “mustn’t” is a Common Mistake (it means you are forbidden from waking up at 6 AM). (c) “haven’t to” is a Structural Error. (a) “shouldn’t” is a Meaning Trap (gives advice, but “don’t have to” perfectly captures the lack of obligation).
2 (c) don’t have to
- Why it is correct: There is no necessity or obligation to rush.
- Distractor Analysis: (a) “mustn’t” is a Common Mistake. (b) “don’t must” is a Structural Error (the negative of must is mustn’t). (d) “can’t” is a Meaning Trap.
3 (d) don’t have to
- Why it is correct: You are free from the obligation of wearing a uniform.
- Distractor Analysis: (c) “mustn’t” is a Common Mistake. (a) “aren’t have to” is a Structural Error. (b) “shouldn’t” is a Meaning Trap.
4 (a) don’t have to
- Why it is correct: Getting up early is completely optional.
- Distractor Analysis: (c) “mustn’t” is a Common Mistake. (b) “doesn’t have to” is a Structural Error (wrong subject agreement; “you” takes “don’t”). (d) “aren’t to” is a Meaning Trap.
5 (c) mustn’t
- Why it is correct: This is a strong roommate rule. Playing loud music while the other is sleeping is strictly prohibited.
- Distractor Analysis: (d) “don’t have to” is a Common Mistake (means “you don’t need to play loud music, but you can if you want,” which ruins the sleep!). (a) “mustn’t to” is a Structural Error (must is followed by the bare infinitive). (b) “don’t need” is a Structural Error (requires “to”).
6 (d) don’t have to
- Why it is correct: Because there is plenty of food, the trip to the supermarket is unnecessary (lack of obligation).
- Distractor Analysis: (c) “mustn’t” is a Common Mistake. (a) “haven’t to” is a Structural Error. (b) “couldn’t” is a Meaning Trap.
7 (a) don’t have to
- Why it is correct: On a weekend, replying to a manager is not required. You have the freedom to ignore it until Monday.
- Distractor Analysis: (b) “mustn’t” is a Common Mistake. (c) “don’t have” is a Structural Error (missing “to”). (d) “shouldn’t” is a Meaning Trap (often people shouldn’t work on weekends, but the grammatical focus here is the absence of the obligation).
8 (b) don’t have to
- Why it is correct: Helping to cook is optional. The speaker is offering to do it alone.
- Distractor Analysis: (c) “mustn’t” is a Common Mistake. (d) “don’t have to helping” is a Structural Error (requires base verb). (a) “wouldn’t” is a Meaning Trap.
9 (b) mustn’t
- Why it is correct: Breaking the mug is strongly forbidden!
- Distractor Analysis: (c) “don’t have to” is a Common Mistake (implies “you don’t need to break it, but go ahead if you want”). (a) “don’t must” is a Structural Error. (d) “haven’t” is a Structural Error.
10 (c) don’t have to
- Why it is correct: The chore is already done, so there is zero obligation to do it again.
- Distractor Analysis: (a) “mustn’t” is a Common Mistake. (d) “haven’t to spend” is a Structural Error. (b) “aren’t need to” is a Structural Error.
11 (a) doesn’t have to
- Why it is correct: “Our team” (singular collective noun) lacks the obligation to submit the report.
- Distractor Analysis: (c) “don’t have to” is a Structural Error (subject-verb agreement mismatch). (b) “mustn’t” is a Common Mistake. (d) “shouldn’t” is a Meaning Trap.
12 (c) don’t have to
- Why it is correct: The roommate is giving the other person the freedom to sleep instead of eating breakfast.
- Distractor Analysis: (a) “mustn’t” is a Common Mistake. (b) “not have to” is a Structural Error. (d) “won’t” is a Meaning Trap.
13 (b) don’t have to
- Why it is correct: There is no rush to choose a movie now; the action is unnecessary at this moment.
- Distractor Analysis: (c) “mustn’t” is a Common Mistake. (a) “don’t have to choosing” is a Structural Error (needs base verb). (d) “aren’t supposed to” is a Meaning Trap.
14 (c) mustn’t
- Why it is correct: Using the broken machine will cause a flood. It is a strict prohibition for safety/property reasons.
- Distractor Analysis: (a) “don’t have to” is a Common Mistake. (b) “mustn’t to” is a Structural Error. (d) “shouldn’t” is a Meaning Trap (too weak for a danger warning).
15 (a) don’t have to
- Why it is correct: The speaker is relieved that leaving the house is not an obligation today.
- Distractor Analysis: (b) “mustn’t” is a Common Mistake. (c) “haven’t to leave” is a Structural Error. (d) “shouldn’t” is a Meaning Trap.
16 (d) don’t have to
- Why it is correct: The sister is taking a taxi, which removes the obligation of picking her up.
- Distractor Analysis: (b) “mustn’t” is a Common Mistake. (c) “don’t need” is a Structural Error (requires “to”). (a) “couldn’t” is a Meaning Trap.
17 (a) mustn’t
- Why it is correct: Deleting the files will cause serious trouble. It is strictly forbidden.
- Distractor Analysis: (b) “don’t have to” is a Common Mistake. (c) “mustn’t deleting” is a Structural Error. (d) “couldn’t” is a Meaning Trap.
18 (d) don’t have to
- Why it is correct: Expressing the current relief of not carrying an obligation.
- Distractor Analysis: (b) “mustn’t” is a Common Mistake. (c) “don’t have” is a Structural Error. (a) “didn’t have to” is a Meaning/Tense Trap (the sentence is in the present tense: “is knowing you…”).
19 (b) don’t have to
- Why it is correct: Eating the leftover salad is not forced. There is an alternative (pizza).
- Distractor Analysis: (c) “mustn’t” is a Common Mistake. (a) “haven’t to eat” is a Structural Error. (d) “shouldn’t” is a Meaning Trap.
20 (d) mustn’t
- Why it is correct: The speaker establishes a humorous but firm rule: talking about work is forbidden to ensure total relaxation.
- Distractor Analysis: (a) “don’t have to” is a Common Mistake (if you use this, it means they are allowed to talk about work if they want to, which ruins the “relaxation rule”). (c) “don’t must” is a Structural Error. (b) “shouldn’t” is a Meaning Trap.
GRAMMAR POINTS TO REMEMBER
1 DON’T HAVE TO (The Magic of Freedom & Lack of Obligation):
- Meaning: It is not necessary to do this. There is absolutely no pressure. However, if you want to do it, you can. It focuses on the absence of a requirement.
- Weekend Context: You don’t have to wake up early. You don’t have to wear a uniform. (You have the freedom to choose!).
- Structure: Subject + don’t/doesn’t have to + Verb (bare infinitive).
2 MUSTN’T (The Strict Rule / Prohibition):
- Meaning: Do not do this. It is a bad idea, against the rules, or dangerous. You have NO choice.
- Weekend Context: You mustn’t wake me up before 10 AM. You mustn’t use the broken washing machine. (Doing these things will cause anger or damage).
- Structure: Subject + mustn’t + Verb (bare infinitive). (Never use “to” after mustn’t).
The Coffee Mug Test: If I say “You don’t have to wash my coffee mug,” it means I am being nice. You can leave it in the sink.
If I say “You mustn’t wash my coffee mug,” it means I am angry or protective. Do not touch my mug!