Cool MateEnquiry vs Inquiry vs Investigation vs Probe vs Request
When to use each in English, with meaning, register, and examples.
Enquiry
Inquiry
Investigation
Probe
Request
| Enquiry | Inquiry | Investigation | Probe | Request | |
|---|---|---|---|---|---|
| Pronunciation | 🇬🇧 /["/ɪnˈkwaɪəri/"]/🇺🇸 /["/ˈɪnkwəri//ɪnˈkwaɪəri/"]/ | 🇬🇧 /["/ɪnˈkwaɪəri/"]/🇺🇸 /["/ˈɪnkwəri//ɪnˈkwaɪəri/"]/ | 🇬🇧 /["/ɪnˌvestɪˈɡeɪʃn/"]/🇺🇸 /["/ɪnˌvestɪˈɡeɪʃn/"]/ | 🇬🇧 //prəʊb//🇺🇸 //proʊb// | 🇬🇧 /["/rɪˈkwest/"]/🇺🇸 /["/rɪˈkwest/"]/ |
| Meaning | A question or a request for information. | A question or asking about something. | Looking into something to find out more about it. | A tool to investigate or explore something deeply. | to ask for something |
| Example | I made an enquiry about the availability of the product. | The teacher encouraged an inquiry into the reasons behind climate change. | The police launched an investigation into the missing person's case. | The scientists sent a probe to study the surface of Mars. | I would like to make a request for a day off next week. |
| Register | Neutral | Neutral | Neutral | Neutral | Neutral |
| How common | Top 5,000 (fairly common) | Top 3,000 (common) | Top 2,000 (common) | Top 2,000 (common) | Top 1,000 (very common) |
| CEFR level | B2 | B2 | B2 | C1 | A2 |
| Part of speech | noun | noun | noun | noun | noun |
| Collocations | detailed, thorough, full, carry out, conduct, have, be underway, take place, begin, report, team, process, at an/the enquiry, during an/the enquiry, in an/the enquiry, a steward’s enquiry, the outcome of an enquiry, the result of an enquiry, exhaustive, extensive, thorough, flood, stream, make, pursue, send, desk, office, service, pending enquiry, enquiry about, enquiry as to, direct an enquiry to somebody, careful, systematic, further, encourage, enquiry concerning, enquiry into, an area of enquiry, a board of enquiry, a commission of enquiry | make an inquiry, conduct an inquiry, primary inquiry, formal inquiry, inquiry process | careful, close, detailed, carry out, conduct, pursue, demonstrate something, reveal something, show something, on investigation, under investigation, investigation into, the subject of an investigation, careful, close, detailed, carry out, conduct, pursue, demonstrate something, reveal something, show something, on investigation, under investigation, investigation into, the subject of an investigation | space probe, medical probe, investigative probe, deep probe | special, legitimate, reasonable, make, put in, send, at somebody’s request, by request, on request, available on request, available upon request, by popular request, special, legitimate, reasonable, make, put in, send, at somebody’s request, by request, on request, available on request, available upon request, by popular request |
| Antonyms | answer, response | answer, response | disregard, neglect, overlook | ignore, avoid | refuse, decline |
| Common mistakes | Confused with 'inquiry'; 'enquiry' is often British English., Using 'enquiry' in informal contexts where 'question' is more suitable., Incorrect pluralization; 'enquiries' should not be replaced with 'enquiries'. | Used incorrectly as 'inquiries' instead of 'inquiry' when talking about one question., Confused with 'enquiry'; remember 'inquiry' is more formal., Not using 'make' to form the phrase 'make an inquiry'. | Confused with 'invest' which means to put money into something., Using 'investigation' as a verb instead of a noun., Mixing up 'investigation' with 'inspector', which refers to a person. | Confused with 'probe' as a verb instead of a noun., Used too generically; may not be appropriate in informal contexts. | Using 'request' with a different preposition, such as 'request for'., Confusing 'request' with 'require'., Not using it in the correct form, like 'requested' instead of 'requesting'. |
| Usage notes | Use 'enquiry' in formal or business contexts when asking for information. In casual conversations, 'question' may be more common. Avoid using 'enquiry' in very informal settings. | Use 'inquiry' in formal situations like business or academic contexts, not in casual conversations. It’s suitable for asking for information or clarification. | Use 'investigation' in formal contexts, like police work or research. Avoid in casual conversations. | Used in scientific and technical contexts, as well as metaphorically in discussions about examining issues. Not commonly used in casual conversation. | Used in polite or formal contexts. It may sound too formal for casual conversations, where simpler words like 'ask' are preferred. |
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Frequently asked questions: Enquiry vs Inquiry vs Investigation vs Probe vs Request
What's the difference between Enquiry, Inquiry, Investigation, Probe, and Request?
Enquiry: A question or a request for information. Inquiry: A question or asking about something. Investigation: Looking into something to find out more about it. Probe: A tool to investigate or explore something deeply. Request: to ask for something
Which is more common: Enquiry, Inquiry, Investigation, Probe, and Request?
Request is the most common in everyday English.
Which is more advanced: Enquiry, Inquiry, Investigation, Probe, and Request?
Probe is the highest level, at C1, on the CEFR scale.
Are Enquiry, Inquiry, Investigation, Probe, and Request the same CEFR level?
Enquiry: B2, Inquiry: B2, Investigation: B2, Probe: C1, Request: A2 on the CEFR scale.
What part of speech are Enquiry, Inquiry, Investigation, Probe, and Request?
Enquiry: noun, Inquiry: noun, Investigation: noun, Probe: noun, Request: noun.
Can you show an example of each?
Enquiry: I made an enquiry about the availability of the product. Inquiry: The teacher encouraged an inquiry into the reasons behind climate change. Investigation: The police launched an investigation into the missing person's case. Probe: The scientists sent a probe to study the surface of Mars. Request: I would like to make a request for a day off next week.
Can I use Enquiry, Inquiry, Investigation, Probe, and Request interchangeably?
Not always. Enquiry, Inquiry, Investigation, Probe, and Request are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.