US AI stock sell-off shakes markets from Wall Street to Asia
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EN: The preposition 'in' is used here to specify the domain or sector in which the 'sell-off' occurred. In financial contexts, 'in' often connects a market action (like a rise, fall, or sell-off) to the specific asset class or industry affected.
We observed a sudden drop in housing prices last month.
EN: The simple past tense ('shook') is used to describe a completed action that occurred at a specific time in the past ('on Tuesday'). 'Shook' is the irregular past tense form of the verb 'shake'.
The unexpected news shook the entire industry yesterday.
EN: In financial journalism, dramatic verbs like 'shook', 'slammed', or 'plunged' are commonly used to describe market movements. This reflects the high-stakes, fast-paced nature of global stock markets where investor sentiment can shift rapidly.
EN: The present perfect tense ('have started') is used to describe an action that began in the past and has relevance or continues to the present moment. It is formed with 'have/has' + past participle.
We have already started the project.
EN: The conjunction 'whether' is used to introduce a noun clause (dependent clause) expressing doubt or choice between alternatives, often acting as the object of verbs like 'question' or 'wonder'.
She wonders whether the store is open today.
EN: In financial markets, the term 'valuation' refers to the analytical process of determining the current (or projected) worth of an asset or a company. When tech valuations soar rapidly, it often sparks debates among global investors about whether a speculative bubble is forming, reminiscent of the dot-com era.
EN: The compound adjective 'tech-heavy' is formed by combining a noun ('tech') and an adjective ('heavy') with a hyphen. This structure is commonly used in English to modify a noun, functioning as a single adjective.
The export-heavy economy is vulnerable to global trade tensions.
EN: The coordinating conjunction 'and' is used here to connect two independent clauses: 'The tech-heavy Nasdaq index opened two percent lower' and 'the Dow and S&P 500 also fell at opening'. A comma is placed before 'and' because it connects two complete thoughts.
The stock market closed early, and investors remained cautious.
EN: The Nasdaq, Dow (Dow Jones Industrial Average), and S&P 500 are the three most closely watched stock market indices in the United States. The Nasdaq is famous for its high concentration of technology and growth stocks, making it highly sensitive to news about artificial intelligence and tech sector earnings.
EN: The Past Perfect tense (had + past participle) is used to describe an action that was completed before another point in time or event in the past. In this sentence, 'had hit' indicates that the stock indices reached record highs before the recent market sell-off occurred.
The company had already launched its new product before the market crashed.
EN: The prepositional phrase 'because of' is used to introduce a reason or cause. It must be followed by a noun, pronoun, or noun phrase (e.g., 'strong interest'), unlike 'because' which is followed by a full clause with a subject and verb.
The flight was delayed because of the heavy rain.
EN: In US financial markets, the 'three major indices' refer to the Dow Jones Industrial Average (the Dow), the S&P 500, and the Nasdaq Composite. They are widely regarded as the primary indicators of the overall health of the US stock market and economy.
EN: The present perfect tense ('have warned') is used here to describe an action that happened at an unspecified time in the past and has relevance to the present situation. It is formed with 'have/has' + past participle.
Many experts have warned about the risks of rapid technological change.
EN: The noun clause starting with 'that' ('that the rush... could be a bubble') acts as the direct object of the verb 'warned'. It contains a complete sentence structure (subject + verb + complement) to express the content of the warning.
She believes that the project will succeed.
EN: The term 'bubble' in economics refers to a situation where the prices of assets (like tech stocks) rise far above their actual value, often driven by hype or speculation, before rapidly collapsing (bursting). This is a direct reference to historical events like the 'dot-com bubble' of the early 2000s.
EN: The verb pattern 'compare A to B' is used to point out similarities between two different things, or to liken one thing to another.
Scientists compare the brain to a powerful computer.
EN: The relative clause 'that burst in the early 2000s' uses the relative pronoun 'that' as the subject to modify the noun phrase 'the dot-com bubble'. 'Burst' is in its past tense form here (burst-burst-burst).
EN: The 'dot-com bubble' (also known as the Internet bubble) was a rapid rise in U.S. technology stock equity valuations fueled by investments in Internet-based companies in the late 1990s. The bubble burst in 2000–2002, causing massive financial losses and the collapse of many tech startups. It remains a classic historical reference point for market speculation.
EN: The phrasal verb 'make up' is used to describe the parts or members that form a whole. It is often followed by a percentage, fraction, or proportion to show composition.
Local residents make up sixty percent of the workforce.
EN: The possessive form ('s) is applied to proper nouns representing organizations or indices (e.g., 'S&P 500's') to indicate ownership or association with a particular attribute like 'total value'.
The company's future looks very bright.
EN: The 'S&P 500' (Standard & Poor's 500) is a stock market index tracking the stock performance of 500 of the largest companies listed on stock exchanges in the United States. The mention of 'Seven technology companies' refers to the 'Magnificent Seven' (Alphabet, Amazon, Apple, Meta, Microsoft, Nvidia, and Tesla), which have come to dominate the US stock market due to the boom in AI technology.
EN: The structure 'make + object + adjective' is a causative construction where 'make' (使、讓) causes the object to enter a specific state described by the adjective.
The sudden noise made the baby crying and nervous.
EN: The noun 'reliance' is commonly paired with the preposition 'on' to indicate the entity being depended upon (reliance on something).
Our reliance on fossil fuels must be reduced.
EN: In financial contexts, 'heavy reliance on a single industry' refers to lack of diversification. This is a common concern in stock markets (like the S&P 500) when a few mega-cap tech stocks (often called the 'Magnificent Seven') drive most of the market's gains, making the entire financial system vulnerable to sector-specific shocks.
EN: Passive Voice (was + past participle): Used when the focus is on the action or the receiver of the action, rather than the doer. In this sentence, 'was triggered' emphasizes the effect (the sell-off) rather than the cause.
The window was broken by the wind.
EN: Preposition 'by' for Agent: In passive sentences, the preposition 'by' is used to introduce the person or thing that performs the action (the agent).
The novel was written by a famous author.
EN: In financial markets, 'Monday' is often a significant day for market reactions, as it is the first trading day after the weekend. Major news that accumulates over the weekend often triggers sharp movements (like a 'sell-off') when the market opens on Monday morning.
EN: Appositives (同位語) are nouns or noun phrases placed next to another noun to identify or explain it. In this sentence, 'the parent company of Google' is an appositive phrase that provides more information about the subject 'Alphabet'. It is set off by commas.
Mr. Smith, my high school English teacher, wrote a book.
EN: The superlative adjective 'worst' (the irregular superlative form of 'bad') is used to describe the single most extreme case among three or more things. Here, it describes the single most negative trading day for Alphabet in a period of over a year.
This is the worst movie I have ever seen.
EN: Alphabet Inc. is the multinational conglomerate created through a corporate restructuring of Google in 2015. While consumers know the brand as 'Google', in financial and stock market contexts, it is referred to by its parent company name, 'Alphabet'.
EN: The non-defining relative clause introduced by ', which' is used to add extra information about the entire preceding clause rather than just the noun before it. In this sentence, 'which' refers to the entire event of 'Two well-known AI researchers leaving the company last week'.
He passed the difficult exam, which surprised everyone.
EN: The past participle 'worried' is used here as an adjective describing the emotional state of the object (investors). It is derived from the transitive verb 'worry' (to cause anxiety to someone).
The bad news made the clients worried about their investments.
EN: The preposition 'by' is used to indicate a deadline or the latest time by which something was completed. In financial contexts, 'by the end of [day/month/year]' specifies the point in time when a certain value or change was reached.
The company hopes to sign the contract by the end of the week.
EN: The verb 'drop' is an intransitive verb here, meaning to decrease in value or amount. It is often followed directly by the amount of decrease (e.g., 'dropped five percent') without needing a preposition like 'by' (though 'dropped by five percent' is also grammatically correct and common).
Temperatures dropped ten degrees overnight.
EN: In financial news, 'by the end of Monday' typically refers to the closing price of the stock market on Monday (usually 4:00 PM Eastern Time in the US). Alphabet, the parent company of Google, is one of the 'Magnificent Seven' tech giants whose stock performance heavily influences major US indices like the S&P 500.
EN: Noun Clause as Object (賓語從句): The word 'that' introduces a noun clause functioning as the direct object of the reporting verb 'said'. It contains a complete sentence structure (subject + verb) and 'that' can often be omitted in informal speech.
The report indicated that consumer spending has increased.
EN: Adjective Complement with Preposition (形容詞搭配介係詞): The adjective 'careful' is followed by the preposition 'about' to specify the object of care or concern ('careful about something').
We must be careful about the decisions we make.
EN: Present Perfect Passive: Formed with 'have/has + been + past participle'. It is used to describe an action that started in the past and has a connection to the present, focusing on the receiver of the action rather than the doer.
The decision has been delayed by the committee.
EN: Passive Voice with 'by': The preposition 'by' is used to introduce the agent (the person or thing performing the action) in a passive sentence.
The project was approved by the manager.
EN: The 'Federal Reserve' (often referred to as 'the Fed') is the central banking system of the United States. In financial news, signals or statements from the Fed regarding interest rates are highly anticipated and can cause immediate, significant reactions in global stock markets.
EN: The sentence uses a noun clause (that-clause) acting as the direct object of the verb 'suggested'. The conjunction 'that' introduces the clause 'it may raise interest rates...' and is often omitted in informal speech, but kept here for formal clarity.
The report suggested that the company would expand its business next year.
EN: The infinitive phrase 'to fight rising inflation' is used as an adverbial of purpose, explaining 'why' the central bank may raise interest rates. 'To' means 'in order to'.
She saved money to buy a new laptop.
EN: In the United States, 'the central bank' refers to the Federal Reserve (often called 'the Fed'). Its decisions on interest rates are closely watched globally because they heavily influence borrowing costs, stock markets, and economic growth worldwide.
EN: Non-defining relative clauses are introduced by 'which' (preceded by a comma) to add extra information about the entire preceding clause. In this sentence, 'which' refers to the whole situation of 'higher interest rates increasing the cost of borrowing'.
The company decided to cut its budget, which worried many employees.
EN: Comparative adjectives (e.g., 'higher') are used to compare two things. Here, 'higher interest rates' implies rates that are higher than the current or previous levels.
Lower prices usually attract more customers to the store.
EN: In financial markets, the decisions of central banks (like the Federal Reserve in the US) regarding interest rates are closely watched. Higher interest rates are a standard tool to combat inflation, but they make borrowing more expensive for companies. This particularly impacts high-growth sectors like technology and AI, which rely heavily on massive capital investments for research and infrastructure.
EN: Noun Clause with 'that': The conjunction 'that' introduces a noun clause functioning as the direct object of the reporting verb 'noted'. It reports a statement or fact.
The report indicated that consumer spending has increased.
EN: Adverbial Clause of Time with 'when': The conjunction 'when' introduces a dependent adverbial clause of time, describing the condition or time under which the action in the main clause occurs.
When interest rates rise, borrowing money becomes more difficult.
Key vocabulary words with IPA pronunciation, definitions, example sentences, and interactive quizzes.
Phrases with type tags, bilingual definitions, usage notes, and example sentences.
A rapid and large-scale selling of securities or commodities, causing a sharp decline in prices.
A rapid rise in US technology stock equity valuations fueled by investments in Internet-based companies in the late 1990s.
The proportion of a loan that is charged as interest to the borrower, typically expressed as an annual percentage.
To reduce speed or activity; to make something happen more slowly.