activated

/ˈæk.tɪ.veɪt/ (bre, ipa) · [ˈæktəvˌetɪd] /ˈæk.tə.veɪt/ (ame, ipa) · [ˈæktəvˌetɪd] /ˈak-tə-ˌvāt/ (ame, mw)

activated — verb

  • activatedpresent simple I / you / we / they
  • activateds3rd person singular
  • activateding-ing form
  • activatededpast simple

1. to make a device, system, or process begin working — for example, starting an al

1.動詞及物B1
釋義

to make a device, system, or process begin working — for example, starting an alarm, turning on a feature in an app, or making a credit card ready for use.

例句

Takeshi activated the smoke alarm by accident when he lit a match near it.

past tense: activated + object + by + trigger event

You need to activate the GPS before the map can show your location.

instructional: need to activate + object

同義詞
  • turn on

    more informal; used for switches and simple controls

  • trigger

    emphasises a sudden cause-effect event

  • start

    broader meaning; can apply to engines or processes

  • enable

    used for software features and settings

反義詞

文法句型

activate + noun phrase

be activated by + noun phrase

用法筆記

Often used in the passive voice (be activated by / when) to describe automatic or triggered actions. The subject is typically a device, a system, or a function that can be turned on.

常見錯誤

❌You need to open the alarm before you leave.
✅You need to activate the alarm before you leave.
💡'activate' means to start or turn on a system; 'open' is for physical objects like doors.
❌I started on the credit card online.
✅I activated the credit card online.
💡'activate' is transitive and takes an object; 'start' without an object has a different meaning.

2. to cause a chemical reaction to happen faster, usually by adding heat, a catalys

2.動詞及物C1
釋義

to cause a chemical reaction to happen faster, usually by adding heat, a catalyst, or another substance — for example, speeding up a reaction by warming a mixture in a laboratory.

例句

The chemist activated the reaction by slowly heating the mixture in a flask.

passive: activated + reaction + by + heating

Enzymes in the yeast are activated when warm water is added to the flour.

passive: are activated when + condition

同義詞
  • trigger

    also used for reactions, but less technical

  • catalyse

    more specific; means to speed up a reaction using a catalyst

反義詞
  • inhibit

    to slow down or stop a reaction

文法句型

activate + noun phrase + by + method

be activated by + heat / catalyst

用法筆記

Primarily used in scientific or laboratory contexts. The agent that causes the faster reaction (heat, a chemical, or light) is usually introduced by the preposition 'by' or 'with'. This sense is rarely used in everyday conversation.

常見錯誤

❌Heat activated the reaction quick.
✅Heat activated the reaction quickly.
💡'quickly' is the adverb needed to modify 'activated'; 'quick' is an adjective.
❌The chemist activated the mixture to heat.
✅The chemist activated the mixture by heating it.
💡'by' followed by a gerund (-ing form) shows the method; 'to heat' is incorrect here.