この記事では語源act（動かす）に関連する英単語を紹介します。
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act /ˈækt/：行動、法律
actは「行動、法律」を意味し、語源はagere（動く）に由来します。同義語はaction, behavior, conduct, activityです。
解説と例文
Act means “things done”, and the etymology comes from agere (moving). The synonyms are action, behavior, conduct, activity. In everyday English, the word “thing” is used rather than “act”.
Let’s see an example sentence.
Violent acts and criminal acts are prohibited by law. Rude acts will bring you unexpected damage. Airlines are strictly vigilant about acts of terrorism. Writing a blog is a creative act.
The second meaning of act is “law”. In particular the word refers to the formal legislation established by the Diet. The synonym “law” means the whole law, while act means a specific law.
Let’s see an example sentence.
The American Civil Rights Act is a law that guarantees the citizenship of black people.
active /ˈæktɪv/：活動的な
activeは「活動的な」を意味し、語源はactus（行動）に由来します。同義語はenergetic, dynamicです。
英語解説と例文
Active means “being busy doing things”, and the etymology comes from actus (action). Synonyms are energetic, dynamic.
Let’s see an example sentence.
Active seniors enjoy hobbies and sports even after retirement. Active people tend to be happier than those who are not. Children are very active and can play with friends all day. Koala, raccoon, leopard, flying squirrel is active at night (= nocturnal). Young men are generally sexually active.
actual /ˈæktʃuəl/：実際の
actualは「実際の」を意味し、語源はactus（行動する）に由来します。同義語はreal, true, practicalです。
解説と例文
Actual means “real”, and the etymology comes from actus (acting). The synonyms are real, true and practical.
“Actual” puts emphasis on the fact, contrasted with estimate and expectations. Let’s see example sentences.
A salaried worker who returns from a business trip calculates the actual expenses. You should use actual examples when making difficult explanations. It is most effective to remember work in actual working. You can learn skills such as saving and self-catering through actual life. Inspection is a task to check the actual number of products.
actually /ˈæktʃuəli/：実際は
actuallyは「実際は」を意味し、語源はactus（行動する）に由来します。同義語はreally, trulyです。
解説と例文
Actually means “really”, and the etymology comes from actus (acting). The synonym is really, truly.
Actually is also used to emphasize the reality. Let’s see an example sentence.
Driving of a car seems to be difficult, but it is actually easy. A Tsundere girl looks unfriendly, but actually kind. Actually collagen has no beautiful skin effect. Natto is sticky and smelly, but actually it is tasty.
agenda /ədʒéndə/：課題
agendaは「組織や政府の問題」を意味し、語源はagere（行う）に由来します。同義語はproblem, issue, questionです。agendaは複数形ですが、常に単数形として扱います。
解説と例文
Agenda means “problems that companies and governments have to deal with”, and the etymology comes from agere (do). The synonyms are problem, issue, question.
Agenda is plural form of agendum, but it is always treated as singular. This is the same as the relationship between media and medium.
Let’s see an example sentence.
If terrorism occurs in the country, countermeasures against terrorism will become top of the agenda. The declining birthrate and aging of society and social security problems in Japan are political agenda.
agent /ˈeɪ.ʤɛnt/：代行業者
agentは「代行業者」を意味し、語源はagere（行動する）に由来します。
解説と例文
Agent means “someone do things instead”, and the origin is derived from agere (act).
Agent means a person or company who does the work as a business instead. Let’s see an example sentence.
Tour agents will arrange for travel on behalf of customers. When borrowing a new room, we will consult a real estate agent. We will ask the insurance agent to join the new insurance. We will ask the forwarding agent to deliver goods to a distant place.
The second meaning of agent is “a person instead of professionals.”
An agent is a person who takes jobs on behalf of professionals or negotiates charges. Western writers use copyright agents for work interactions with publishers. By delegating complicated tasks to agents, authors can focus on their own work.
Agent is also used in the world of sports and entertainment. Sports players and celebrities leave it to the agent without doing price negotiation on their own.
agency /ˈeː.ʤən.si/：代理店、政府機関
agencyは「代理店、政府機関」を意味し、語源はagere（動かす）に由来します。
解説と例文
Agency means “a business providing a particular service”, and the origin is derived from agere (move).
Agent has strong nuances of people, but agency has a strong meaning of corporation. Let’s see example sentences.
Companies ask the advertising agency to advertise their products. If you want a marriage partner, consult on marriage agency. If you want a new job, you should go to an employment agency. The press purchase news from the news agency.
The second meaning of agency is “government organization”. Let’s see example sentences.
The Tourism Agency promotes the tourism industry in Japan. The Japan Meteorological Agency provides weather information through the media. The Financial Services Agency is monitoring the financial transactions of the market. The National Police Agency will manage the entire police as the police top. The National Tax Agency conduct tax administration.
agile /ˈædʒəl/：素早い
agileは「素早い」を意味し、語源はagere（動く）に由来します。同義語はnimble, quick, speedyです。
解説と例文
Agile means “quick in movement”, and the etymology comes from agere (moving). The synonyms are nimble, quick and speedy.
Let’s see example sentences.
Wild cats are very agile, so ordinary people can not catch it. An agile child is good at tagging. Even with manual labor, agile action is required.
Agile is also used in software development. Agile development is a method of making an overall system in a short period and repeating it until it is completed. This short development period is called iteration. The period is usually about 1 to 4 weeks.
agitate /ˈædʒətèɪt/：要求する
agitateは「要求する」を意味し、語源はagere（動かす）に由来します。同義語はdemandです。
解説と例文
Agitate means “to argue strongly”, and the etymology comes from agere (move). Synonym is demand.
Let’s see an example sentence.
The labor union agitates the company to raise the wage. Anti-war people in Japan agitated against the Security Treaty. Media always agitate for political reform, but will never take responsibility for it.
exact /ɪgzˈækt/：正確な
exactは「正確な」を意味し、語源はex（外）とagere（動かす）に由来します。原義はラテン語のexigere（要求する）で、同義語はcorrect, accurate, preciseです。
解説と例文
Exact means “accurate”, and the origin is derived from ex (outside) and agere (moving). The original meaning is Latin exigere (request), and the synonyms are correct, accurate, precise.
Let’s see example sentences.
When a corpse is found, the police first identify the exact cause of death. The witness who discovered the corpse tells the police the exact location and time. The digital clock will display exact time. The exact replica is on display at the museum.
Working in factory line is very boring, because they always do the exact same thing. It is difficult to make exact copies of Japanese notes. Freelance’s way of living is the exact opposite of civil servants.
interact /ìnṭɚˈækt/：交流する
interactは「交流する」を意味し、語源はinter（間）とact（行動）に由来します。
解説と例文
Interact means “to talk or work together”, and the origin is derived from inter (between) and act (action).
Let’s see an example sentence.
We human beings refine sociability by interacting with others at school and workplace. We feel calm by interacting with animals. A friendly person can feel free to interact with any person.
react /riˈækt/：反応する
reactは「反応する」を意味し、語源はre（再び）とact（行動する）に由来します。同義語はrespondです。
解説と例文
React means “to respond”, and the etymology comes from re (again) and act (to act).Synonym is respond.
Let’s see an example sentence.
Our eyes react to light, our ears react to sounds. Pain sensation reacts to pain. Even if others speak ill of you, you should not react immediately. Adolescent children react against their parents’ ideas. In the hospitality industry, it is required to react quickly.
transact /trænsˈækt/：ビジネスを行う
transactは「ビジネスを行う」を意味し、語源はtrans（通じて）とact（行動）に由来します。原義はラテン語のtransgere（達成する）で、同義語はdo business with, deal withです。
解説と例文
Transact means “to do business with someone”, and the origin is derived from trans (through) and act (action). Original meaning is Latin transgere (achieve), and the synonyms are “do business with” and “deal with”.
Let’s see an example sentence.
In modern times anyone can transact online. People who are fluent in English can transact with foreign people.