6.5.3: Should not/Must not/Don't Have to
- Page ID
- 271297
\( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)
\( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)
\( \newcommand{\id}{\mathrm{id}}\) \( \newcommand{\Span}{\mathrm{span}}\)
( \newcommand{\kernel}{\mathrm{null}\,}\) \( \newcommand{\range}{\mathrm{range}\,}\)
\( \newcommand{\RealPart}{\mathrm{Re}}\) \( \newcommand{\ImaginaryPart}{\mathrm{Im}}\)
\( \newcommand{\Argument}{\mathrm{Arg}}\) \( \newcommand{\norm}[1]{\| #1 \|}\)
\( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\)
\( \newcommand{\Span}{\mathrm{span}}\)
\( \newcommand{\id}{\mathrm{id}}\)
\( \newcommand{\Span}{\mathrm{span}}\)
\( \newcommand{\kernel}{\mathrm{null}\,}\)
\( \newcommand{\range}{\mathrm{range}\,}\)
\( \newcommand{\RealPart}{\mathrm{Re}}\)
\( \newcommand{\ImaginaryPart}{\mathrm{Im}}\)
\( \newcommand{\Argument}{\mathrm{Arg}}\)
\( \newcommand{\norm}[1]{\| #1 \|}\)
\( \newcommand{\inner}[2]{\langle #1, #2 \rangle}\)
\( \newcommand{\Span}{\mathrm{span}}\) \( \newcommand{\AA}{\unicode[.8,0]{x212B}}\)
\( \newcommand{\vectorA}[1]{\vec{#1}} % arrow\)
\( \newcommand{\vectorAt}[1]{\vec{\text{#1}}} % arrow\)
\( \newcommand{\vectorB}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)
\( \newcommand{\vectorC}[1]{\textbf{#1}} \)
\( \newcommand{\vectorD}[1]{\overrightarrow{#1}} \)
\( \newcommand{\vectorDt}[1]{\overrightarrow{\text{#1}}} \)
\( \newcommand{\vectE}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash{\mathbf {#1}}}} \)
\( \newcommand{\vecs}[1]{\overset { \scriptstyle \rightharpoonup} {\mathbf{#1}} } \)
\( \newcommand{\vecd}[1]{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}} \)
\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)Modals with “Not”: Should Not, Must Not, Do Not Have To
Negative Modal of Advice
Should not
- In order to show that something is not advisable (a bad idea) we can use “should not” or “shouldn’t”
For example:
- You shouldn’t stay up too late the night before a test.
Modals for Lack of Obligation
Don't/Doesn't/ Didn't have to
- If something is not necessary or not an obligation, we use the modal verb “do/does not have to.” Make sure the verb agrees with the subject.
For example:
- In the United States, children do not have to go to school on Saturdays, but many adults have to work.
- Common Question: Do children have to go to school on Saturdays? No, they don't.
- Maggie doesn't have to study tonight because she studied all day.
- Common Question: Does Maggie have to study tonight? No, she doesn't.
To put the modal in past tense, simply use the phrase “DID not have to.”
For example:
- For homework last night, we had to read Units 4 and 6, but we didn't have to read Unit 5
- Question: Did we have to read Unit 5 last night? No, we didn’t.
As always, modals are followed by the base form of a verb. The “to” in “do not have to” is not an infinitive. It is part of the modal itself.
Subject + do/does not have to + base verb + ...
Modals of Prohibition
Must Not
Finally, in order to show that something is prohibited or not allowed, we use “must not.” For example:
- Students must not copy their work from the Internet. It's illegal!
- Children, you must not go in a stranger's car. It's dangerous!
Using “must not” is very serious and not very common in North American English. There is no question form or past tense form. It is useful when people in authority are giving instructions or explaining to people what they must not do in a formal way. It is more common in writing than in speaking.
- Drivers must not drive on the left side of the road in North America.
- You must not drink alcohol before you drive. You could cause an accident.
Note: In American English “mustn’t” is generally not used.
Exercise 5.5: Must Not or Don't Have To
Choose the best modal for each sentence.
- Students ________ pay to park on campus
A. must not
B. don't have to
- In the United States, employers ________ discriminate against women or minorities. It's against the law.
A. must not
B. don't have to
- Shops ________ sell cigarettes to children.
A. must not
B. don't have to
- This show is free! You ________ buy a ticket.
A. must not
B. don't have to
- You ________ drive over the speed limit.
A. don't have to
B. must not
- You ________ live in the United States to take a class at a university. You can take courses online.
A. must not
B. don't have to
- You ________ pass a test to ride a bicycle.
A. must not
B. don't have to
- You ________ buy a textbook for this course – the textbooks are free.
A. don't have to
B. must not
Exercise 5.6: Should Not or Must Not
Choose the best modal form to complete the sentence.
1. Students ________ park in the staff parking spaces. They may get a ticket.
A. should not
B. must not
2. You ______ eat too much fast food. It can cause you to gain weight.
A. should not
B. must not
3. According to pool rules, children _______ enter the swimming pool alone.
A. should not
B. must not
4. Drivers _______ drive without a valid driver’s license.
A. should not
B. must not
5. Teenagers ______ drive at night until they become more experienced.
A. should not
B. must not
6. Children ______ go to bed late on school nights.
A. should not
B. must not
Exercise 5.7: Shouldn't, Don't Have to or Must not
1. Airline passengers ___________________________ carry a paper boarding pass. They can save their boarding pass in their cell phone.
2. Airline passengers ___________________________ put their prescription medicines in their checked baggage. If the bags get lost, they will not have their medicine.
3. Airline passengers ___________________________ check their carry-on bags. They can store them in the overhead bins.
4. Airline passengers ___________________________ smoke in the airplane.
5. Parents ___________________________ leave young children alone at home.
6. Students ___________________________ come to campus on Sunday.
7. Children ___________________________ disobey their parents.
8. Students ___________________________ wait until the night before a test to study.
9. You ___________________________ wear a suit or dress to attend classes.
10. Shoppers ___________________________ go to a store to buy everything. Most things are available to buy online.
Modals with "Not": Must Not Do not Have To from UVIC is licensed for use under CC BY-NC-SA 4.0 International.