Grammar Rule: Idioms Have No Rules | Complete List


Grammar Rule: Idioms Have No Rules | Complete List


Idiom questions are likely to appear at least a couple of times, but they are different than any other question on the ACT English. That is because English idioms don’t conform to a set of specific rules and you have to rely on your familiarity with specific phrases.

In this article, we will define the concept of an idiom, describe most common types of idiom questions, suggest strategies to identify and correctly answer idiom questions, and provide you with an extensive list of idioms to help you study.

What is an Idiom?

Idioms are phrases or expressions that do not follow any specific rules. Each idiom is unique and most people think of idioms as expressions whose figurative meanings are different from literal meanings. Examples of this type of idiom include “actions speak louder than words,” “I’ve got your back,” and “are we on the same page?” ACT, however, does not test you on these everyday expressions, it tests you on different types of idioms.How are Idioms Tested on ACT English?

Grammar Rule: Idioms Have No Rules | Complete List

Instead of testing you on the types of expressions I referenced above, the ACT tests you on prepositional idioms and idioms with gerunds and infinitives.

Prepositional Idioms

For prepositional idioms, you must know which preposition to use based on the context of a sentence. For example, you should say that your “wonder about” something, not “wonder on” something. You’re “suspicious of” something, not “suspicious by” something. The rule is that there is no specific rule to determine the correct preposition to use. You must either be familiar with the phrase or rely on what “sounds right” to you. For example,

Incorrect:         Predictably, after Ryan decided to return the damaged bicycle to the store, the store manager was outraged for Ryan’s behavior.

This is an example of a typical sentence that you might encounter on ACT English. There is no violation of any specific grammar rule; however, the phrase “outraged for” is incorrect. The sentence should read:

Correct:           Predictably, after Ryan decided to return the damaged bicycle to the store, the store manager was outraged by Ryan’s behavior.

The proper idiomatic expression is “outraged by.” Because there is no rule that allows you to determine the correct expression, familiarity with these phrases will help you to identify idiom errors on the ACT.

Idioms with Gerunds and Infinitives

Gerunds and Infinitives are other types of idioms commonly tested on the ACT.

Gerunds are verbs that are used as nouns and end in “ing.” Examples include talking, speaking, listening.

Infinitives are verbs that re used as nouns and are constructed by adding the word “to” + a verb. Examples include to do, to speak, to talk, to listen.

For these types of idioms, you need to know which preposition to use and whether to use a gerund or an infinitive.

Sometimes, depending on the context, it is acceptable to use an infinitive or a gerund.

Gerund:           Matt neglected doing his homework.

Infinitive:         Matt neglected to do his homework.

While both of these sentences are correct, here’s an example with an idiom error.

Incorrect:         Nicole will succeed in to graduate from college.

The phrase “succeed in to graduate” is incorrect. The correct expression is:

Correct:           Nicole will succeed in graduating from college.

Unfortunately, there is no rule that will teach you that “succeed in graduating” is correct while “succeed in to graduate” is not. You must use your intuition and prior knowledge of idioms. Here’s another example:

Incorrect:         Gina decides leaving the group when we go out.

Correct:           Gina decides to leave the group when we go out.

Let’s look at a couple of actual ACT idiom questions.

ACT English Example




The correct answer is D. The correct idiomatic expression is “I sat across the aisle from..”

Idiom Questions can be Difficult/Easy – Reasons Why

Grammar Rule: Idioms Have No Rules | Complete List

Why They Are Difficult

While other grammar questions follow specific patterns and rules that can be applied to any sentence, idiom questions specifically test your knowledge of idiomatic expressions. In the English language, there are thousands of idioms and it is neither practical, nor effective to memorize each one.

In addition, non-native English speakers and ESL students are less likely to be able to identify idiom errors because knowledge of idioms is built through long term exposure to them.

Why They Are Easy

Idiom questions are the types of questions when you should rely on what “sounds right”. You do not have to know any rules. If you are familiar with a specific idiom tested on ACT English, you can confidently recognize and identify idiom errors.

ACT English Tips for Idioms Questions

  • If a preposition, a gerund, or an infinitive is underlined, check for idiom errors.
  • If all of the answer choices are prepositions – the question may be testing idioms.
  • Make a list of idioms that appear on your practice tests.
  • Periodically review and familiarize yourself with the list of idioms below.

List of ACT Idioms

While there are thousands of idioms in the English language, almost all idiom questions on the ACT involve prepositional idioms or idioms with gerunds / infinitives. Below is the list of the most common prepositional idioms as well as idioms with gerunds / infinitives to help you study. While it’s good to be familiar with the types of idioms tested on ACT English, spending hours memorizing them is not practical because they only appear once or twice on each test.

However, it is a good idea to review these lists of phrases periodically to become more familiar with them. Reviewing these lists has a built-in benefit of improving your intuitive grasp of and recognition of idiom errors when you encounter idiom questions on the ACT.

Idioms from Real ACT Prep Guide

Come to a conclusion 

~Come to a halt 

Come to an end

Earned a living from / by doing

In the dusk

Modeled on

Principles of 

Such as

Prepositional Idioms

Grammar Rule: Idioms Have No Rules | Complete List

List #1

About Against As At By For
anxious about advise against celebrate as aim at accompanied by Advocate for
ask about argue against regard as arrive at amazed by ask for
bring about count against see as laugh at confused by blame for
curious about decide against view as look at followed by famous for
hear about defend against succeed at go by known for
think about go against impressed by last for
talk about rebel against organized by meant for
worry about struck by named for
necessary for
pay for
ready for
responsible for
tolerance for
strive for
wait for
watch for


List #2

From Into In On Over Of
abstain from enter into engage in base on argue over approve of
different from look into fall in love draw on rule over capable of
excuse from inquire into in A as in B focus on talk over certain of
far from read into interested in impose on think over characteristic of
hear about succeed in insist on cure of
obvious from take in move on deprive of
protect from prey on die of
rely on a fan of
~in danger of
in the hope of
in recognition of
made up of
a model of
an offer of
on the border of
remind of
a selection of
a source of
suspicious of
take advantage of
an understanding of
a wealth of

List #3

To With
able to agree with
accustomed to bargain with
adapt to correlate with
adhere to familiar with
admit to identify with
adjacent to in keeping with
agree to interfere with
as opposed to sympathize with
belong to trust with
central to
come to
contribute to
devoted to
in addition to
in contrast to
listen to
object to
prefer A to B
partial to
reluctant to
reply to
see to
similar to
a threat to
try to
unique to


Gerunds vs. Infinitives

Grammar Rule: Idioms Have No Rules | Complete List

Verbs followed by a Gerund Prepositions followed by a Gerund Verbs followed by an Infinitive
accuse of before agree
admire for after attempt
allow without choose
appreciate condescend
capable of dare
complete decide
concentrate on deserve
confess to encourage
consider expect
delay fail
describe intend
discourage from love
discuss mean
dislike neglect
effective at pffer
enjoy plan
escape prepare
finish promise
forbid refuse
imagine scramble
insist on seem
permit strive
plan on swear
postpone tend
refrain from threaten
report want

Next Steps

Looking for an overview of ACT English section, check out our article about what’s actually tested on ACT English.

To continue your efforts to improve your ACT English score, check out our article on 5 concepts you must know to ace ACT English.

Having trouble with punctuation? We have an article about commas and other punctuation to help you navigate this frequently tested topic.

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