10 exercises — how "come to think of it" signals a sudden, relevant recollection during standups, design reviews, and postmortems, its fixed grammatical form, and its close relative "now that you mention it."
Quick reference
Come to think of it: introduces a memory or fact that surfaces mid-discussion and reframes what was just said
Fixed form: "come" + "to think" + "of it" — never conjugated or reordered
Distinct from the literal verb phrase "come to think of X as Y" (to gradually form an opinion)
Close relative: "now that you mention it" (credits the other speaker's remark as the trigger)
Register: conversational, common in standups and chat threads
0 / 10 completed
1 / 10
A standup update reads: "We haven't seen this error before. ___ , a similar stack trace showed up in last month's logs too." Which phrase best signals a fact suddenly recalled mid-conversation?
Come to think of it is a fixed idiom marking a fact or memory that occurs to the speaker unexpectedly, often mid-sentence or mid-conversation, correcting or adding to what was just said. "Think of it as" introduces an analogy or reframing ("think of it as a cache, not a database"), a different function. "To think that" introduces an expression of astonishment or disbelief about a fact ("To think that this bug has been there for years!"), not a recollection. "Thinking about it" is a plausible-sounding paraphrase but not the fixed idiomatic form used as a discourse marker.
2 / 10
Which sentence uses "come to think of it" correctly?
"We assumed the outage was network-related. Come to think of it, the same region had a similar incident last quarter" is correct — a fact is recalled mid-discussion that adds a new angle to the conversation. It cannot introduce a direct command ("please deploy"), take an internal "that"-clause ("that the bug is fixed"), or be conjugated as a normal verb phrase ("came to think of it as") — as a discourse marker it is invariant, always in this exact imperative-looking but fixed form.
3 / 10
Fill the blank: "I thought this was a new bug. ___ , I remember fixing something almost identical six months ago."
Come to think of it has a fixed, unalterable word order. The other three options are scrambled, meaningless rearrangements; like other fixed discourse markers ("for what it's worth," "needless to say"), the internal order of the words is not flexible.
4 / 10
Which pair correctly distinguishes "come to think of it" from "now that you mention it"?
Both phrases mark a sudden recollection triggered by the current conversation, but with a subtle difference in attribution. "Come to think of it" presents the recollection as arising from the speaker's own reflection. "Now that you mention it" explicitly credits the other person's preceding remark as the trigger: "'Did the retry logic change recently?' 'Now that you mention it, yes — we bumped the max attempts last sprint.'" In many contexts they are interchangeable, but the second is specifically responsive to another speaker.
5 / 10
A design review comment reads: "This pattern looks unfamiliar at first. ___ , I saw the same approach in the payments service." Which best completes the sentence?
Come to think of it is the correct, standard fixed order. All three distractors scramble the required sequence ("come" + "to think" + "of it") into invalid, non-existent phrases.
6 / 10
Which sentence contains an error in the use of "come to think of it"?
"She came to think of it as an unnecessary rewrite" uses "come to think of it" as a regular, conjugatable verb phrase meaning "she eventually regarded it as" — this is a different, literal construction ("come to think of X as Y," meaning "to gradually form an opinion"), not the fixed, invariant discourse marker. As a discourse marker, "come to think of it" is never conjugated or given a subject other than the implicit speaker; it always appears in exactly this fixed form. The other three sentences use the genuine discourse marker correctly.
7 / 10
Choose the sentence where "come to think of it" is best replaced by "actually, now that I think about it" without changing the meaning.
"We assumed this was an isolated incident. Actually, now that I think about it, three other teams reported the same timeout last week" preserves the meaning: a recollection that reframes the preceding assumption. The other options misuse the phrase as a command softener, a literal verb phrase about deliberation ("had to come to think of it"), or an instruction to categorize something ("think of it as a design flaw"), none of which match the fixed discourse-marker function.
8 / 10
A postmortem note states: "We initially ruled out a DNS issue. ___ , the timing lines up with the DNS provider's maintenance window." Which best fits?
Come to think of it is the correct, fully fixed form. "Come thinking of it" incorrectly substitutes the gerund "thinking" for the infinitive "to think." "Come to thought of it" incorrectly substitutes the noun "thought" for the infinitive verb "think." "Come think of it" drops the required "to" before "think," which is not a valid shortening of this idiom.
9 / 10
Which register note about "come to think of it" is accurate?
"Come to think of it" is a conversational phrase, most at home in spoken meetings, standups, and informal chat threads — exactly the settings where a relevant memory or connection tends to surface mid-discussion. It carries no inherent criticism; it simply flags that new, relevant information has just occurred to the speaker. It is almost always sentence-initial (or clause-initial after a full stop), introducing the newly recalled fact, not appearing at the end.
10 / 10
Which sentence best demonstrates "come to think of it" introducing a relevant memory that reframes an earlier assumption?
"We assumed the slow query was new. Come to think of it, I remember seeing the exact same execution plan flagged in a code review two months ago" is the idiomatic use: an assumption is immediately reframed by a memory that surfaces mid-discussion. The other options misuse the phrase as a command softener, insert it awkwardly into a noun phrase ("as slow"), or attach an invalid "that"-clause directly to it — none of which match its fixed, stand-alone discourse-marker function.