Improved air quality linked to better mental development in toddlers, study finds
Listen to Course
0:00
0:00
EN: The sentence uses the Present Perfect tense ('has found') followed by a noun clause introduced by 'that'. The present perfect indicates that a past research finding has relevance to the present, while the noun clause acts as the direct object of 'has found'.
Recent studies have shown that regular exercise reduces stress levels.
EN: The passive construction 'is connected to' functions as a relational phrase meaning 'associated with' or 'linked to', followed by a noun phrase expressing the outcome or related factor.
Poor sleep quality is connected to difficulty concentrating.
EN: Columbia University, located in Upper Manhattan, New York City, is an Ivy League research institution known for leading high-impact public health and environmental studies.
EN: Passive Voice in the Past Simple ('was/were + past participle'): It is used here because the focus is on the research ('The study') rather than the researchers. 'Led' is the irregular past participle of the verb 'lead'. The agent performing the action is introduced with the preposition 'by'.
The project was completed by a group of talented engineers.
EN: Prepositional Phrase of Location ('at + organization/institution'): The preposition 'at' is used to denote a specific institution, organization, or workplace where a person or team conducts their work.
She works as a senior researcher at the National Cancer Institute.
EN: In academic and scientific reporting in English-speaking media, it is customary to mention the principal investigator by their formal title (e.g., 'Professor') followed by their affiliated research center or university. This establishes the authority and institutional backing of the findings.
EN: The noun phrase 'the effects of [something] on [someone/something]' is a common academic and formal pattern used to describe the impact or influence of a cause upon a subject.
Scientists are monitoring the effects of global warming on polar bears.
EN: The preposition 'for' combined with a duration ('for more than twenty years') expresses the continuous duration of an action. The phrase 'more than' acts as a quantifier modifier meaning 'over' or 'exceeding'.
She has worked at the hospital for more than ten years.
EN: The past participle 'disadvantaged' is used as an adjective modifying the noun 'communities', describing groups that face social or economic hardships.
The charity provides free meals to disadvantaged children in the city.
EN: The preposition 'in' indicates location. Here, two prepositional phrases are nested: 'in disadvantaged communities' shows the type of environment, followed by 'in northern Manhattan and the South Bronx' to specify the precise geographical locations.
Volunteers worked in temporary clinics in rural villages and remote towns.
EN: Northern Manhattan (including neighborhoods like Harlem and Washington Heights) and the South Bronx have historically been lower-income areas with higher rates of air pollution, heavy traffic corridors, and childhood asthma, making them critical focal points for public health and environmental justice research.
EN: Passive Voice in Past Simple ('were assessed'): Used when the focus is on the people or things receiving the action rather than who performed it. Formed by 'was/were' + past participle.
All participants were interviewed before the project began.
EN: Adverbial Clause of Time ('when they were...'): Introduced by the conjunction 'when' to specify the time at which the main clause's action took place.
He learned to swim when he was five years old.
EN: In English academic and journalistic writing, expressing multiple ages sequentially as 'one, two, and three years old' is a concise way to avoid repeating 'years old' for each number.
EN: The relative pronoun 'that' introduces a defining relative clause ('that included memory...') modifying the noun phrase 'cognitive test scores'. It functions as the subject within the relative clause.
The survey collected data that showed significant changes in student behavior.
EN: Parallel structure is used when listing multiple items sharing the same grammatical form. Here, three noun phrases are joined by commas and 'and': 'memory', 'problem-solving', and 'language comprehension'.
The training program focuses on leadership, communication, and conflict resolution.
EN: In developmental psychology and pediatric public health studies, 'cognitive tests' for toddlers (such as the Bayley Scales of Infant and Toddler Development) typically evaluate early milestones in memory, basic problem-solving, and receptive/expressive language rather than academic skills.
EN: The reporting verb 'found' is followed by a 'that'-noun clause acting as the direct object ('that pollution... had negative effects...'). This pattern is standard in academic and news reporting to summarize empirical findings.
Doctors found that regular exercise reduced the risk of heart disease.
EN: The collocation 'have an effect on [something]' means to cause a change or produce an impact on someone or something. Adjectives like 'negative', 'positive', or 'significant' typically modify 'effects'.
Lack of sleep has negative effects on your immune system.
EN: The present perfect tense ('has improved') is used with time expressions like 'over the past two decades' to describe an action or change that started in the past and continues to be relevant up to the present moment.
Public transportation in the city has expanded significantly over the past five years.
EN: The transition adverb 'However' is placed at the beginning of the sentence followed by a comma to signal a contrast with the previous information.
However, recent efforts have brought noticeable improvements.
EN: In the late 20th century, New York City faced severe air pollution from vehicle emissions and heavy heating oil used in residential buildings. Substantial policy changes—such as the Clean Air Act standards, vehicle emissions programs, and phasing out dirty heating fuels—led to dramatic improvements in urban air quality over the 2000s and 2010s.
EN: The present perfect tense ('have reduced') is formed with 'have/has' + past participle. It connects a past action or change to the present situation, emphasizing the lasting result.
Recent safety campaigns have reduced traffic accidents in our neighborhood.
EN: The phrase 'by as much as + [amount/percentage]' is used to emphasize a surprisingly large degree or quantity of difference or reduction. The preposition 'by' indicates the margin or extent of change.
Solar panel costs have fallen by as much as seventy percent over the last decade.
EN: In New York City, yellow cabs are an iconic symbol of urban transport. Historically, thousands of gas-powered taxis idling in traffic contributed significantly to roadside emissions, leading the city to mandate hybrid or clean-fuel vehicle transitions starting in the late 2000s.
EN: A non-defining relative clause begins with a comma and 'which', giving extra, non-essential information about the noun ('Heavy fuel oils'). The sentence would still make complete grammatical sense without it.
Old diesel buses, which produced a lot of smoke, have been taken off the road.
EN: The present continuous passive ('are being + past participle') describes an action currently in progress that is happening to the subject. The phrase 'replace A with B' means to substitute B in place of A.
The outdated computers are being replaced with newer models.
EN: In New York City, many older residential and commercial buildings traditionally relied on high-polluting 'heavy heating oil' (such as No. 4 and No. 6 oil). City regulations (like NYC Clean Heat) phased out these dirty fuels in favor of natural gas, biodiesel, or ultra-low-sulfur oil to significantly improve urban air quality.
EN: The preposition 'by' is commonly used after verbs of increase or decrease (such as drop, fall, increase, rise) to indicate the margin or extent of change (e.g., 'dropped by half').
The company's profits decreased by 20% this quarter.
EN: The correlative structure 'between A and B' is used to define a specific time span or range linking two points in time.
The museum was renovated between 2010 and 2012.
EN: 'Fine particle pollution' commonly refers to PM2.5 in environmental science and public policy discussions. In major metropolitan areas like New York, monitoring both PM2.5 and nitrogen dioxide (NO2) has been central to urban clean-air initiatives targeting vehicular and heating emissions.
EN: The structure 'The good news is that...' uses a noun clause introduced by 'that' functioning as a predicative complement (subject complement) after the linking verb 'is'.
The good news is that everyone passed the final exam.
EN: The subordinating conjunction 'as' is used here to indicate parallel change, meaning 'while' or 'in proportion to the way that' something happens concurrently.
As people grow older, they tend to become more patient.
EN: Reported Speech with Backshift: When reporting past statements or thoughts using a past reporting verb ('said', 'wanted'), the verbs in the subordinate clauses typically shift back into a past form (e.g., 'will' becomes 'would').
She said that she would visit her grandparents next week.
EN: Indirect Yes/No Questions with 'if': The conjunction 'if' (or 'whether') introduces an embedded noun clause acting as the object of a verb like 'know', 'wonder', or 'ask'. Word order remains declarative (subject + verb), not inverted.
The doctor wanted to know if the medicine worked effectively.
EN: In academic journalism, it is common to quote researchers' hypotheses and findings using reporting verbs like 'said', followed by multi-clause structures that outline the cause-and-effect relationships being tested.
EN: Adverb placement: In simple active sentences, frequency or manner adverbs like 'clearly' often sit immediately before the main verb to emphasize the action or state described.
The report clearly highlighted several critical errors.
EN: The simple past tense ('showed') is used here to report the completed findings and outcomes of a specific scientific study.
Previous experiments showed similar outcomes across all age groups.
EN: In scientific reporting, phrases like 'positive connection' or 'positive correlation' mean that two variables increase together (here, better air quality corresponds to higher cognitive scores), rather than simply meaning 'good' news.
EN: The reporting verb 'suggests' is followed by a 'that'-noun clause acting as the direct object. Inside this clause, the gerund phrase 'reducing pollution' functions as the subject.
The report indicates that eating vegetables improves overall physical health.
EN: The adverb 'even' is used here to add emphasis before a time adverbial clause ('before they are born'), highlighting an extreme or surprising condition.
She continued to work hard, even when she was exhausted.
EN: In academic and science journalism, cautious reporting verbs like 'suggests' or 'indicates' are favored over absolute claims like 'proves', reflecting the scientific convention that individual studies offer evidence rather than definitive proof.
Key vocabulary words with IPA pronunciation, definitions, example sentences, and interactive quizzes.
Phrases with type tags, bilingual definitions, usage notes, and example sentences.
The degree to which the air is clean, clear, and free from pollutants.
Related to or associated with something.
The growth and maturation of intellectual, emotional, and cognitive capabilities.
Pollution consisting of tiny solid or liquid particles suspended in the air (such as PM2.5).
To cause something to happen or result in a particular outcome.