must be absent

USAGE SUMMARY

The phrase "must be absent" is correct and usable in written English.
It can be used to indicate that someone or something is required to not be present in a particular situation or context. Example: "In order to maintain the integrity of the experiment, all participants must be absent during the control phase."

✓ Grammatically correct

Science

Academia

News & Media

Wiki

Encyclopedias

Formal & Business

Human-verified examples from authoritative sources

Exact Expressions

24 human-written examples

As a consequence, all spontaneous movements and elicitable reflexes must be absent in the state of 'brain death'.

Nature

TAs are expected to be present at their posted office hour; if they must be absent, they are responsible for finding someone to cover for them.

Columbia University

Terpenes, found in some evergreen trees and ferns, are similar in chemical structure to substances called juvenile hormones, which are present in all insects during larval development but must be absent during the transition from egg or larva to adult.

Britannica

(6) Must be absent from duty for purposes relating to his or her adoption of a child, including appointments with adoption agencies, social workers, and attorneys; court proceedings; required travel; and any other activities necessary to allow the adoption to proceed.

Cornell University

Microorganisms must be absent from histopathology specimens and aspirates of affected tissue, including presumed abscess cavities.

Insights into Imaging

According to the WHO standards, thermotolerant coliforms must be absent in a 100-ml water sample.

Applied Water Science

Human-verified similar examples from authoritative sources

Similar Expressions

35 human-written examples

Counting induced subgraphs on k vertices as opposed to any subgraphs on k vertices means that all the edges between the k vertices in the subgraph must be present in the larger graph, and absent edges in the subgraph must also be absent in the larger graph.

Bioinformatics

During the eight-year emergency, speaking Gikuyu was punishable with the cane but he promised his mother, Wanjiku, that "I must never be absent from school, however hungry we were".

The Guardian - Books

By Sidney Lear and E. B. White The New Yorker, August 1 , 1931 P. 7Harvard alumnus who had taken his wife and son with him to the twenty-fifth reunion stopped the cab in which they were riding back to their hotel, listened to the solemn tolling of the bell, explained that he mustn't be absent and hurried off - to a stag party.

The New Yorker

5 6 Given that pain is so prevalent among young people with CP, strategies to reduce it must be either absent or inadequate.

Archives of Disease in Childhood

Thus, a criterion was established that a gene must be flagged absent in less than 20% of the samples and its expression data must have a standard deviation greater than the 25% percentile of the population.

BMC Genomics

Expert writing Tips

Best practice

When using "must be absent", ensure the context clearly indicates what conditions necessitate the absence. This adds clarity and avoids ambiguity.

Common error

Avoid using "must be absent" in casual conversation or informal writing. Opt for more natural alternatives like "can't be here" or "is away" to maintain an appropriate tone.

Linguistic Context

The phrase "must be absent" functions as a modal verb phrase expressing a strong necessity or requirement for something or someone to be not present. As Ludwig AI confirms, it is grammatically correct and suitable for use in various contexts. This necessity can stem from rules, conditions, or desired outcomes.

Expression frequency: Common

Frequent in

Science

60%

Academia

20%

News & Media

10%

Less common in

Wiki

5%

Encyclopedias

3%

Formal & Business

2%

Ludwig's WRAP-UP

In summary, the phrase "must be absent" is a grammatically sound and relatively common expression used to denote a mandatory state of absence. As confirmed by Ludwig AI, the phrase is versatile and finds application across multiple domains, but particularly within scientific and academic writing. When using the phrase, clarity regarding the context necessitating the absence is essential. While appropriate for formal communication, be cautious about using "must be absent" in informal settings where more natural alternatives are preferable. Remember that "must be absent" indicates a requirement, contrasting with weaker suggestions like "should be absent".

More alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

must not be present

Directly states the prohibition of something being in a particular place or condition.

needs to be missing

Emphasizes a necessity for something to be lacking, focusing on the need rather than obligation.

should be unavailable

Indicates a recommendation or expectation that something is not accessible or present.

has to be excluded

Highlights the act of preventing something from being included or present.

is required to be gone

Stresses the mandatory aspect of something's absence, using a more descriptive tone.

is essential to omit

Focuses on the importance of leaving something out or not including it.

is imperative to exclude

Highlights the critical need to keep something away or prevent its presence.

is obligate to stay away

This alternative uses a more formal tone, highlighting the binding nature of the absence.

needs to be precluded

This indicates that something has to be prevented in advance.

ought to be lacking

This suggests a weaker obligation or expectation of absence.

FAQs

How can I rephrase "must be absent" to sound more formal?

For a more formal tone, consider using phrases like "is required to be absent", "it is imperative that... is not present", or "should be unavailable". These alternatives provide a similar meaning with a more elevated register.

What are some less formal alternatives to "must be absent"?

In casual contexts, you can replace "must be absent" with phrases such as "can't be here", "is away", or "won't be there". These options are more suitable for everyday conversation.

When is it appropriate to use "must be absent" in writing?

The phrase "must be absent" is suitable in formal writing, scientific reports, legal documents, and official guidelines where a condition of absence is critical and non-negotiable.

Is there a difference between "must be absent" and "should be absent"?

"Must be absent" indicates a requirement or obligation, while "should be absent" suggests a recommendation or expectation. The former implies a stricter necessity than the latter.