Idioms and Prepositions

• Recall the correct preposition for the dozen most commonly tested verb + preposition and adjective + preposition pairs
• Distinguish standard idiomatic usage from plausible-sounding but non-standard alternatives
• Identify preposition errors quickly on the ACT English section without re-reading the full sentence
• Recognize idiom traps inside longer underlined portions (where only the preposition is wrong)

Idiom questions on the ACT test fixed expressions: pairings of a verb, noun, or adjective with one specific preposition, and a few fixed two-part structures. They count as Conventions of Standard English (usage), and they almost always come with the most common English stem, 'Which choice makes the sentence most grammatically acceptable?' There is no logical rule: English just uses these pairings. Learn this short list of high-frequency pairs: different from, interested IN, capable OF (capable of doing, never capable to do), responsible for, based ON, rely ON, consist OF, familiar with, similar TO, opposed TO, prefer one thing TO another, a preference for, an interest IN, in contrast TO or with, and agree with a person but agree TO a proposal. The fixed two-part structures must keep both halves in the expected form: not only ... but also, either ... or, neither ... nor, both ... and, between ... and (never between ... or), as ... as, and so ... that. Two habits keep you from being fooled by your ear. (1) When a preposition is underlined, find the word it attaches to and confirm the pairing against one you know: 'opposed to', not 'opposed against'. (2) If you cannot name a pairing that makes the original wrong, do not change it just because it sounds unusual; NO CHANGE is right on many idiom items. Watch the verb form that follows the preposition: a preposition is followed by an -ing form ('insisted on paying', 'capable of finishing'), so 'insisted to pay' is an idiom error. 'Different from' is the form the ACT treats as standard. The ACT-hard version: the wrong preposition sits inside a long underlined portion where the rest is fine ('in response of the complaints, the council'), or the choices pair a noun and a verb that take different prepositions ('a preference for' but 'prefer to'), so look at the exact word the preposition attaches to.

• Idioms have no rule. Make a flashcard deck and drill them in 5-minute bursts over the week.
• Do not change a preposition just because it 'sounds off.' Confirm or reject it against a pairing you actually know. If you cannot name the rule, NO CHANGE is often correct.
• Choose 'different from' on the ACT; it is the form the test treats as standard.
• A preposition is followed by an -ing form: 'insisted on paying', not 'insisted to pay'.
• When a preposition is underlined, find the exact word it attaches to (a verb, a noun, or an adjective) and check that pairing.