An architect opens a design review with: "_____ we need is a circuit breaker between the API gateway and the downstream services." Which nominal relative clause correctly introduces the solution?
What is correct. "What we need is..." is a nominal relative clause (also called a "wh-cleft") that functions as the subject of the sentence. It is equivalent to "The thing that we need is...". "What" introduces the clause when the noun is unspecified — the most common pattern for emphasising a solution or recommendation in technical discussions. Which and that introduce relative clauses modifying a specific noun, not nominal clauses. How introduces manner clauses ("how we do it"), not solution framing.
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A developer explains a bug to the team: "_____ happens is the cache layer returns stale data when the TTL is set to zero." Which nominal relative clause introduces the explanation?
What is correct. "What happens is..." is a nominal relative clause used to introduce an explanation of a process or behaviour. It is particularly useful in technical presentations and debugging discussions because it foregrounds the event before the explanation. "What happens is X" is equivalent to "The thing that happens is X." Which requires a noun antecedent. That introduces a complement clause ("I know that...") not a subject clause with this structure. Where introduces a locative clause.
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A tech lead says in a sprint retrospective: "_____ concerns me most is the lack of test coverage in the payment module." Which is correct?
What is correct. "What concerns me most is..." is a nominal relative clause functioning as the subject. It focuses attention on the speaker's concern. This structure is very common in professional discussions to introduce a key point with emphasis. Note: "It that" is not a valid English structure. "Which concerns me most" would need a noun antecedent ("The issue which concerns me most is..."). "That concerns me most" cannot function as a standalone subject clause.
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An engineer writes in a postmortem: "_____ made the outage worse was the absence of automated failover." Which nominal relative clause correctly frames the escalating factor?
What is correct. "What made the outage worse was..." is a nominal relative clause identifying the factor that caused escalation. It is the standard structure for highlighting root causes or contributing factors in incident analysis. The structure "X was Y" (where X is a "what-clause") is a wh-cleft — it gives emphasis to Y while naming X. "Which" needs a noun antecedent. "That which" is archaic. "The thing" is informal and less efficient.
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A product manager presents a trade-off: "_____ we're seeing is a 20% increase in throughput at the cost of 5% higher error rates." Which nominal relative clause introduces the observed result?
What is correct. "What we're seeing is..." introduces observed data or results in a presentation or discussion. It is a nominal relative clause functioning as the subject. This is standard in technical presentations for reporting metrics, observations, or test results. The structure emphasises the finding. Which requires a specific noun antecedent. Where is locative. How would introduce a manner ("how we achieve this"), not a description of results.
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An architect explains a design decision: "_____ we're trying to avoid is tight coupling between the frontend and backend." Which structure is correct?
What is correct. "What we're trying to avoid is..." is a nominal relative clause that introduces the design goal or constraint. The "what-clause" acts as the subject, and the complement ("tight coupling") is the focus of the sentence. This is extremely natural in design discussions — it frames the problem before stating it. That would create a subordinate clause ("I know that..."), not a subject clause. Which needs an antecedent. Whatever implies "anything at all" — too vague for a specific design goal.
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Which sentence uses a nominal relative clause incorrectly?
Option C is incorrect. "What the service must be fault-tolerant" is ungrammatical. Nominal relative clauses with "what" require a predicate structure: "What the service must be is fault-tolerant" (with "is") would be correct. Without the copula "is", the clause has no main predicate. Options A, B, and D all follow the correct "What + clause + is + complement" or "What + clause + verb + object" structure.
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A senior engineer writes in a design doc: "_____ I propose is a three-tier caching strategy: L1 in-process, L2 Redis, L3 CDN." Which nominal relative clause introduces the proposal?
What is correct. "What I propose is..." introduces the speaker's recommendation using a nominal relative clause as the subject. It is a confident and clear framing device in design documents and architecture proposals. The structure puts the proposal in focus position. Which needs an antecedent. That creates a subordinate clause ("I argue that my proposal is...") but cannot open a subject clause in this way. "The proposal" would work but is less elegant and loses the first-person framing.
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A team lead says in a retrospective: "_____ worked well this sprint was the daily async standups — we should keep that." Which nominal relative clause introduces the positive feedback?
What is correct. "What worked well was..." is the standard nominal relative clause for positive retrospective feedback. It frames the subject (the daily async standups) as the focus of what succeeded. This structure is used in both retrospectives and postmortems to highlight what went well or poorly. That cannot open a subject clause in this structure. Which needs an antecedent. "It is" begins an it-cleft, which would require restructuring ("It was the daily async standups that worked well").
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A developer says in a code review discussion: "_____ I find problematic is this nested callback — it's going to be hard to test." Which nominal relative clause expresses the reviewer's concern?
What is correct. "What I find problematic is..." is a nominal relative clause that expresses the reviewer's specific concern as the subject of the sentence. It is direct, professional, and focuses attention on the identified issue. This structure avoids hedging ("I think maybe this is a problem") while also avoiding bluntness ("This is wrong"). It is the preferred framing in constructive code review. Which, That, and Where cannot function as the subject of a nominal clause in this structure.
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David, a technical writer, wrote in a PR description:
'The feature we're implementing is the one that allows users to upload large files.' Which nominal relative clause correctly introduces the described functionality?
This question focuses on using 'that' to describe the feature's current status. The relative clause is functioning similarly to an adjective, providing details about what the feature *is*. Options A and B are potential consequences or priorities, while option D describes a benefit, not the feature itself.
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David, a technical writer, wrote in a PR description:
'The feature we're implementing is the one that allows users to upload large files.' Which nominal relative clause correctly introduces the described functionality?
This question focuses on using 'that' to describe the feature's current status. The relative clause is functioning similarly to an adjective, providing details about what the feature *is*. Options A and B are potential consequences or priorities, while option D describes a benefit, not the feature itself.
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Sarah, a DevOps engineer, commented on a failing deployment pipeline: 'What's causing the increased latency is the lack of proper resource allocation during peak hours.' Which nominal relative clause correctly introduces the cause of the problem?
This question tests your understanding of using nominal relative clauses to explain a cause. The clause 'the lack of proper resource allocation' functions as the subject of 'what's causing.' Incorrect options either misidentify the cause or use incorrect grammatical structures. The core concept is that the relative clause identifies *what* is responsible for the latency.
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During a Slack discussion about performance bottlenecks, Mark said: 'The issue we're seeing is that the database query isn't optimized for large datasets.' Which nominal relative clause correctly introduces the problem being discussed?
Here, 'the issue we're seeing' acts as the subject of 'is.' This is a common structure for nominal relative clauses describing a situation. The other options are either parts of the problem or related concepts, but don't function as the main clause introducing it. Focus on how the relative clause identifies *what* constitutes the issue.
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During a standup meeting, Ben said: 'The feature we're prioritizing is improved error handling.' Which nominal relative clause describes the feature being discussed?
This question focuses on a common workplace scenario – discussing priorities. 'The feature we're prioritizing' is the subject of 'is.' It clearly identifies *what* is being given priority. Remember that nominal relative clauses often function as subjects or objects within a sentence, providing further information about the noun they modify.
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A tech lead is explaining a proposed architecture: 'What we need is a centralized logging system for all our services.' Which nominal relative clause correctly introduces the suggested solution?
The correct answer uses 'the' to specify a particular instance of 'centralized logging system.' This is important when referring back to something previously mentioned or defined. Options B and C are redundant, and option D lacks the necessary grammatical structure.
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A QA engineer is investigating a bug report. 'The unexpected behaviour we're seeing is the intermittent loss of data during synchronization.' Which nominal relative clause describes the observed issue?
This question tests understanding of nominal relative clauses introducing a description. 'The unexpected behaviour…' is the core of the description, and 'intermittent loss of data' provides crucial detail about *how* that behaviour manifests. Options B & D are irrelevant to the main clause's focus.
What will I practise in "Nominal Relative Clauses in Tech Discussions — Grammar Exercise"?
Practice using 'what we need is...', 'what happens is...', 'what matters is...' structures to frame technical problems and solutions.
How many exercises are in this module?
This module has 17 multiple-choice exercises, each with instant feedback and a full explanation of the correct answer.
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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.