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Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.

Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com
must left
Grammar usage guide and real-world examplesUSAGE SUMMARY
"must left" is not a correct and usable phrase in written English.
Instead, you can use the phrase "must leave" which means "must go" or "must depart". For example, "It's time to go - we must leave now".
⚠ May contain grammatical issues
Wiki
News & Media
Alternative expressions(7)
Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Human-verified examples from authoritative sources
Exact Expressions
1 human-written examples
Your Lyrics should be powerful and complex, and usually must left a lot of possible interpretations and meanings on the air.
Wiki
Human-verified similar examples from authoritative sources
Similar Expressions
54 human-written examples
"He must leave.
News & Media
And Mubarak must leave.
News & Media
must leave office.
News & Media
But you must leave".
News & Media
So he must leave again.
News & Media
"You must leave," he said.
News & Media
All passengers must leave now".
News & Media
We must leave this country".
News & Media
You must leave".
News & Media
We must leave.
News & Media
Expert writing Tips
Best practice
Always use the correct form of the verb after "must". "Must" is a modal verb and should be followed by the base form of the verb (e.g. "must leave"), not the past participle (e.g. "left").
Common error
Avoid using past participle forms after "must". Remember that "must" requires the base form of the verb. For example, it's "must go", not "must went", and "must leave", not "must left".
Source & Trust
87%
Authority and reliability
1.8/5
Expert rating
Real-world application tested
Linguistic Context
The phrase "must left" is grammatically incorrect. The correct form is "must leave", where "must" functions as a modal verb indicating obligation or necessity, and "leave" is the base form of the verb. The Ludwig AI confirms this grammatical error.
Frequent in
News & Media
35%
Wiki
32%
Science
30%
Less common in
Formal & Business
1%
Encyclopedias
1%
Reference
1%
Ludwig's WRAP-UP
The phrase "must left" is grammatically incorrect; the correct form is "must leave". "Must" is a modal verb and requires the base form of the verb. As Ludwig AI points out, using "must left" is a grammatical error that should be avoided. While the examples include instances of the erroneous phrase, they highlight the importance of using the correct grammatical structure. To express obligation or necessity to depart, use "must leave" or consider alternatives such as "has to go", "needs to exit", or "is required to leave". Always ensure the base form of the verb follows "must" for grammatically sound writing.
More alternative expressions(6)
Phrases that express similar concepts, ordered by semantic similarity:
must depart
Replaces "left" with "depart", offering a formal synonym for leaving.
is required to leave
Replaces "must" with a more descriptive phrase indicating an obligation to depart.
has to go
Uses a simpler and more direct phrasing to indicate the necessity of leaving.
should exit
Suggests leaving with an emphasis on the action of exiting a place or situation.
is obliged to go
Emphasizes the obligatory nature of leaving, using more formal language.
needs to exit
Indicates a necessity to leave using the word "exit", suggesting a departure from a specific location.
is bound to leave
Highlights that leaving is inevitable or certain.
is compelled to depart
Uses strong wording to indicate a forced or very necessary departure.
is under an obligation to leave
Expresses leaving as a formal or legal requirement.
must get going
Implies a sense of urgency or initiation of departure.
FAQs
What does "must leave" mean?
"Must leave" signifies an obligation or necessity to depart from a place or situation. It indicates that someone is required or compelled to go.
How can I use the phrase "must leave" in a sentence?
You can use "must leave" to express the need for someone to depart. For instance, "I must leave now to catch my train" or "He must leave the country immediately".
What are some alternatives to "must leave"?
Alternatives include "has to go", "needs to exit", "is required to leave", or "should exit", depending on the context.
Which is correct, "must leave" or "must left"?
"Must leave" is the correct form. "Must" is a modal verb and should be followed by the base form of the verb. "Must left" is grammatically incorrect. Always use "must leave" instead.
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Table of contents
Usage summary
Human-verified examples
Expert writing tips
Linguistic context
Ludwig's wrap-up
Alternative expressions
FAQs
Source & Trust
87%
Authority and reliability
1.8/5
Expert rating
Real-world application tested