6.5.4.1: Alternatives to "Must" "Must Not" and "Have to"
- Page ID
- 256037
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\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)The Imperative Verb Form and Related Expressions
Along with modal verbs like "must," "must not," and "have to," there are a number of other common ways to express permission, obligation, and prohibition.
The imperative is particularly effective for direct commands and prohibitions, offering a simpler alternative to modal verbs in many contexts. In addition, expressions like "can" and "be allowed to," are used to express permission, prohibition, obligation, and prohibition in English. Here’s how they compare and relate:
1. Expressing Permission
"Can" and "be allowed to/permitted to" indicate that someone has the freedom or right to do something:
- You can leave early if you finish your work. (permission)
- Employees are allowed to take breaks every two hours. (formal permission)
- Visitors are permitted to take photos in the museum. (formal or official permission)
2. Expressing Prohibition
"Can't" and "not allowed to/not permitted to" indicate that something is forbidden or not permitted:
- You can't park here. (prohibition)
- Students are not allowed to use their phones during exams. (formal prohibition)
- Smoking is not permitted in this building. (formal or official prohibition)
3. Expressing Obligation
a) Using "Must" and "Have to"
"Must" and "have to" explicitly express obligation and are more formal:
- You must wear a seatbelt at all times. (obligation)
- Employees have to complete training before starting work. (obligation)
b) Using the Imperative Form
- The imperative form can replace "must" or "have to" to express obligation in a direct and less formal way.
- You must follow the instructions. → Follow the instructions.
- You have to wear a helmet. → Wear a helmet.
4. Expressing Prohibition with "Must Not" and the Imperative
"Must not" expresses strong prohibition and is formal:
- You must not touch the wires.
- Students must not cheat on exams.
- The imperative form can replace "must not" for direct and conversational prohibition:
- Don’t touch the wires.
- Don’t cheat on exams.
5. Imperative vs. Modal Verbs
Tone and Formality:
- Modal verbs like "must" and "have to" are more formal, suitable for official contexts.
- The imperative is more direct and conversational, ideal for spoken instructions or informal settings.
- Formal: Employees must adhere to the safety guidelines.
- Imperative: Adhere to the safety guidelines.
- Emphasis:
- The imperative can sound more forceful due to its directness.
- You must leave immediately. → Leave immediately!
- The imperative can sound more forceful due to its directness.
The Imperative Verb Form and Related Expressions written with the assistance of Chat GPT.
Read and Learn
You are going to read a sign that resembles signs you might see on a campground. The sign uses many of the above ways to express permission, obligation and necessity. Pay attention to the forms as you read. (Note: The phrases "bare necessities" and "bare facts" are a play on words. The word "bare" means "basic and simple," but it is pronounced the same the word as "bear.")
Images from....
Exercise 5.7: Changing Verb Forms to Modal Auxiliary Forms
Exercise: Below are sentences from the reading written in imperative verb forms as well as other constructions. For this exercise, you will change the sentences to statements using "Must," "Must Not," and "Have to"
Change the following imperative sentences into statements using "must," "must not," or "have to." Write complete sentences in the space to the right.
- Check out by noon.
- Leave before the security gate closes at 9:00 p.m.
- No open fires are allowed during a fire ban.
- No loud music at campsites at any time.
- Place all garbage in bear-proof bins.
- Do not feed the bears.
- Never approach a bear.
- Do not run unless you are close to a secure place.
- Move away slowly keeping the bear in view.
Extension Activity 
Exercise 5.8: Focus on Unwritten Rules
Our communities have many rules that are communicated by symbols instead of lists of words and sentences like the ones Claire made for the campground. Here are three examples you might recognize:
For each photo below, the rule we know but isn’t stated in words could be
For this activity, extend or stretch your learning outside English class.
- Go out in your community.
- Use your cellphone to take two or more pictures of symbols that are really messages about rules.
- Save the pictures in your cell phone.
- Identify a rule that each symbol communicates.
- Write the rule in three different ways.
- Bring your sentences to class.
When you return to class, share your pictures and sentences with your group.
Images and Expansion Activity from In the Community- An_Intermediate-Integrated-Skills shared under a CC BY-SA license and authored, remixed, and/or curated by Faculty of Foundational, Career, and Intercultural Studies.