5 exercises — a/an/the with technical nouns: "an API", "the database", "a singleton", zero article for product names and uncountable nouns.
0 / 5 completed
1 / 5
A developer writes in a ticket: "We need to add _____ API endpoint that accepts _____ JSON payload and returns _____ HTTP 200 response."
Option B is correct. Two important rules:
a vs an with abbreviations: the choice depends on the pronunciation of the first letter, not its spelling. "API" is pronounced "ay-pee-eye" — it starts with the vowel sound /eɪ/, so it takes an. "HTTP" starts with "aitch" /eɪtʃ/, a vowel sound — so an HTTP. "A JSON payload" — "JSON" starts with /dʒ/ (consonant sound) — so a. Acronym article rule: an API, an IDE, an MVP, an SLA, an ORM; but a URL (/jʊ/), a UI (/juː/), a SQL query (if pronounced "sequel").
a/an vs the: the first three nouns are being introduced generically — no specific endpoint is implied — so use the indefinite article.
2 / 5
An architecture document states: "_____ load balancer distributes requests across _____ three backend servers. _____ server that fails is automatically removed from _____ pool."
Option C is the most natural. Article rules at work:
"A load balancer" — the document is describing the system generically, as a type of component, not referring to one specific, previously mentioned load balancer. Use indefinite article.
"three backend servers" — no article needed before a cardinal number in this context ("distributes across three servers").
"A server that fails" — a generic/hypothetical server, not a specific identified one. Use indefinite.
"the pool" — "pool" has already been conceptually introduced (the pool is part of the system being described), so the definite article is appropriate — it refers to the pool that belongs to the load balancer described above.
3 / 5
A README introduction reads: "This library provides _____ caching layer built on _____ Redis. _____ caching layer supports _____ LRU eviction and _____ TTL configuration."
Option B is correct. Key rules demonstrated:
"a caching layer" — first mention, introduced as a feature of the library. Indefinite article.
"Redis" (no article) — proper nouns and product/brand names (Redis, PostgreSQL, Kubernetes, Docker, GitHub) take no article. Never "a Redis" or "the Redis" unless you mean a specific installation: "the Redis instance in staging".
"The caching layer" — second mention, now identified and specific. Switch to definite article.
"LRU eviction and TTL configuration" (no article) — technical features listed as uncountable/abstract concepts take zero article. Compare: "supports LRU eviction" vs "has a good LRU eviction policy".
4 / 5
A code review comment says: "_____ performance of this query is acceptable, but using _____ singleton pattern here would be _____ mistake."
Option C is correct.
"The performance" — performance here is specified ("of this query") — we know exactly which performance we mean. Use "the" with nouns that are uniquely identified by a following prepositional phrase. "The performance of this query", "the complexity of the algorithm", "the latency of the endpoint".
"a singleton pattern" — the singleton pattern is being named as a type/category ("using a singleton pattern" = using this kind of pattern). Indefinite article for a category reference.
"a mistake" — one of many possible mistakes, introduced for the first time. Indefinite article.
Note: Option D is wrong because abstract nouns like "performance" and "pattern" in specific contexts do need articles.
5 / 5
An incident report summary states: "_____ outage began at 14:23 UTC. _____ root cause was _____ memory leak in _____ authentication service. _____ engineering team resolved _____ issue within 47 minutes."
Option C is correct, and this exercise illustrates how articles shift from indefinite to definite within a single paragraph:
"An outage" — first mention, introduced into the discourse. Indefinite. (Starts with vowel sound /aʊ/, so "an").
"The root cause" — every outage has exactly one root cause in an incident report; the concept of "root cause" is treated as unique and already implied by the context. Use "the". In postmortem writing, "the root cause" is a near-fixed phrase.
"a memory leak" — one of many possible causes; introduced for the first time.
"the authentication service" — a specific, named service known to the reader (it's "our" auth service).
"The engineering team" and "the issue" — both are uniquely identified entities already known in context.