5 exercises — choose between which, that, who, and where, and decide when commas are required, in precise technical documentation.
0 / 20 completed
1 / 20
A doc describes one specific endpoint among many. Which sentence uses a correct defining (restrictive) relative clause?
Defining clauses identify, and take no commas: A defining (restrictive) relative clause specifies which endpoint we mean, so it is essential and is not set off by commas. Both that and which are acceptable in defining clauses (American style often prefers that; British style allows either), but option A wrongly adds commas around that. Option C uses what, which cannot introduce a relative clause modifying a noun. Option D has only one comma, leaving the punctuation unbalanced.
2 / 20
There is only one API gateway, and you want to add extra, non-essential information about it. Which sentence is correct?
Non-defining clauses add extra info, with commas and "which": Because there is only one gateway, the clause merely adds detail rather than identifying which gateway — this is a non-defining (non-restrictive) clause. It must be enclosed in commas and must use which (or who for people), never that. Option A omits the commas, turning it into a defining clause that wrongly implies several gateways. Option C has unbalanced commas. Option D incorrectly uses that in a non-defining clause.
3 / 20
You are describing the engineer responsible for a service. Which relative pronoun is correct?
"Who" for people as the subject: When the relative pronoun refers to a person and is the subject of the clause (the engineer performs the owning), use who. Which is for things, not people. What cannot introduce a relative clause modifying a noun. Whom is the object form and would only be correct if the person were the object of the verb (e.g. the engineer whom we consulted) — here the engineer is the subject, so who is required.
4 / 20
In which sentence can the relative pronoun be correctly omitted (a contact/zero relative clause)?
Omitting the relative pronoun when it is the object: The relative pronoun may be dropped only when it is the object of the relative clause. In option B, that is the object of edited (we edited the file), so it can be omitted: The config file we edited broke the deployment. In options A, C, and D the relative pronoun is the subject of its clause (that caused, which crashed, which throws), so it cannot be removed without leaving the clause without a subject.
5 / 20
You want to describe the data centre location of a deployment. Which relative adverb correctly introduces the clause?
"Where" as a relative adverb for places: When the relative clause refers to a place and replaces a prepositional phrase (in the region), the relative adverb where is the clean choice: the region where the service is deployed. Option A drops the necessary preposition in after which. Option C uses who, which is for people. Option D commits a double-reference error by keeping both which … in and the resumptive pronoun it.
6 / 20
SeniorDev commented on the PR: 'The authentication flow requires a UUID. Ensure the generateUUID() function is used consistently across all services.' Which sentence correctly uses a relative clause to clarify this requirement?
This question tests understanding of *defining* relative clauses. Option 1 correctly uses 'which' to introduce a clause specifying the action needed. The other options incorrectly use non-essential relative clauses or misinterpret the meaning of the sentence. It's crucial to identify the core requirement being stated – that UUID generation needs consistency.
7 / 20
Slack message from QA_Lead: 'I'm seeing intermittent failures with the PaymentService. The logs show errors related to network latency – specifically, timeouts when calling the ExternalGateway API. The root cause is likely increased load on the gateway.' Which sentence best uses a relative clause to describe the problem?
This question focuses on using relative clauses to explain a complex technical issue. Option 0 correctly identifies 'which' as introducing the clause explaining *why* the timeout is happening. The other options present the same information in an awkward or less clear way. It's important to clearly link the cause and effect.
8 / 20
Code Reviewer wrote: 'The new UserProfileService returns a JSON object with fields like firstName and lastName. It's crucial that these are always validated against the schema defined in schema.json.' Which relative pronoun is most appropriate to use here?
This question tests the correct usage of relative pronouns. 'Which' is the best choice because it refers to a specific thing – the JSON object returned by the service. 'That' can be used but is often less preferred in this context, and 'who' and 'whose' are inappropriate for non-human objects. Using which clearly connects the description of the JSON object with its validation requirement.
9 / 20
During a Standup update, you said: 'The team is working on improving the performance of the DataPipeline. It's currently bottlenecked by excessive database queries.' Which sentence correctly uses a non-defining relative clause to provide further information?
This question examines non-defining relative clauses. Option 2 correctly uses 'which' to add extra detail about the issue being addressed – specifically, that it's a priority for the team. The other options either incorrectly modify the core statement or use inappropriate phrasing. Using which provides context without fundamentally changing the sentence's meaning.
10 / 20
In a PR description for a new feature in the MonitoringService, you want to explain how it integrates with existing metrics. Which sentence best uses a relative clause?
This question tests the use of relative clauses for clarity in a PR description. Option 2 clearly states *how* the integration is achieved using 'which', providing a concise explanation that avoids repetition. The other options are less direct or awkwardly phrased, making it harder to understand the key functionality.
11 / 20
SeniorDev commented on the PR: 'The authentication flow requires a UUID. Ensure the generateUUID() function is used consistently across all services.' Which sentence correctly uses a relative clause to clarify this requirement?
This question tests understanding of *defining* relative clauses. Option 1 correctly uses 'which' to introduce a clause specifying the action needed. The other options incorrectly use non-essential relative clauses or misinterpret the meaning of the sentence. It's crucial to identify the core requirement being stated – that UUID generation needs consistency.
12 / 20
Slack message from QA_Lead: 'I'm seeing intermittent failures with the PaymentService. The logs show errors related to network latency – specifically, timeouts when calling the ExternalGateway API. The root cause is likely increased load on the gateway.' Which sentence best uses a relative clause to describe the problem?
This question focuses on using relative clauses to explain a complex technical issue. Option 0 correctly identifies 'which' as introducing the clause explaining *why* the timeout is happening. The other options present the same information in an awkward or less clear way. It's important to clearly link the cause and effect.
13 / 20
Code Reviewer wrote: 'The new UserProfileService returns a JSON object with fields like firstName and lastName. It's crucial that these are always validated against the schema defined in schema.json.' Which relative pronoun is most appropriate to use here?
This question tests the correct usage of relative pronouns. 'Which' is the best choice because it refers to a specific thing – the JSON object returned by the service. 'That' can be used but is often less preferred in this context, and 'who' and 'whose' are inappropriate for non-human objects. Using which clearly connects the description of the JSON object with its validation requirement.
14 / 20
During a Standup update, you said: 'The team is working on improving the performance of the DataPipeline. It's currently bottlenecked by excessive database queries.' Which sentence correctly uses a non-defining relative clause to provide further information?
This question examines non-defining relative clauses. Option 2 correctly uses 'which' to add extra detail about the issue being addressed – specifically, that it's a priority for the team. The other options either incorrectly modify the core statement or use inappropriate phrasing. Using which provides context without fundamentally changing the sentence's meaning.
15 / 20
In a PR description for a new feature in the MonitoringService, you want to explain how it integrates with existing metrics. Which sentence best uses a relative clause?
This question tests the use of relative clauses for clarity in a PR description. Option 2 clearly states *how* the integration is achieved using 'which', providing a concise explanation that avoids repetition. The other options are less direct or awkwardly phrased, making it harder to understand the key functionality.
16 / 20
SeniorDev commented on the PR: 'The authentication flow requires a UUID. Ensure the generateUUID() function is used consistently across all services.' Which sentence correctly uses a relative clause to clarify this requirement?
This question tests understanding of *defining* relative clauses. Option 1 correctly uses 'which' to introduce a clause specifying the action needed. The other options incorrectly use non-essential relative clauses or misinterpret the meaning of the sentence. It's crucial to identify the core requirement being stated – that UUID generation needs consistency.
17 / 20
Slack message from QA_Lead: 'I'm seeing intermittent failures with the PaymentService. The logs show errors related to network latency – specifically, timeouts when calling the ExternalGateway API. The root cause is likely increased load on the gateway.' Which sentence best uses a relative clause to describe the problem?
This question focuses on using relative clauses to explain a complex technical issue. Option 0 correctly identifies 'which' as introducing the clause explaining *why* the timeout is happening. The other options present the same information in an awkward or less clear way. It's important to clearly link the cause and effect.
18 / 20
Code Reviewer wrote: 'The new UserProfileService returns a JSON object with fields like firstName and lastName. It's crucial that these are always validated against the schema defined in schema.json.' Which relative pronoun is most appropriate to use here?
This question tests the correct usage of relative pronouns. 'Which' is the best choice because it refers to a specific thing – the JSON object returned by the service. 'That' can be used but is often less preferred in this context, and 'who' and 'whose' are inappropriate for non-human objects. Using which clearly connects the description of the JSON object with its validation requirement.
19 / 20
During a Standup update, you said: 'The team is working on improving the performance of the DataPipeline. It's currently bottlenecked by excessive database queries.' Which sentence correctly uses a non-defining relative clause to provide further information?
This question examines non-defining relative clauses. Option 2 correctly uses 'which' to add extra detail about the issue being addressed – specifically, that it's a priority for the team. The other options either incorrectly modify the core statement or use inappropriate phrasing. Using which provides context without fundamentally changing the sentence's meaning.
20 / 20
In a PR description for a new feature in the MonitoringService, you want to explain how it integrates with existing metrics. Which sentence best uses a relative clause?
This question tests the use of relative clauses for clarity in a PR description. Option 2 clearly states *how* the integration is achieved using 'which', providing a concise explanation that avoids repetition. The other options are less direct or awkwardly phrased, making it harder to understand the key functionality.
What will I practise in "Relative Clauses in Technical Documentation — Grammar Exercises"?
Practise defining vs non-defining relative clauses with which, that, who, and where in technical docs. 5 intermediate exercises with detailed explanations.
How many exercises are in this module?
This module has 20 multiple-choice exercises, each with instant feedback and a full explanation of the correct answer.
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How is this different from reading an article on the same topic?
Articles explain grammar rules in prose; this exercise tests and reinforces those rules through active recall with immediate feedback — the two work best together.
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Every exercise is written by the CoderSlingo team, drawing on real workplace English used in IT roles, then reviewed for accuracy and clarity.