This pair is a genuine grammar test, not just a vocabulary choice — one takes an object, the other never does.
"Strike up" names the act of beginning an interaction — it's transitive and takes a noun object, like "a conversation." "Hit it off" names the resulting chemistry between two people once talking has already started, and takes no noun object.
A grammar-and-meaning pairing, not a synonym choice
"Strike up" always needs an object — you strike up something. "Hit it off" never takes one — you hit it off with someone, describing how well the interaction is going, not what caused it to start.
A learner who blends the two produces sentences like "we struck up well" (missing the required object) or "we hit it off a conversation" (adding an object the phrase doesn't take) — both ungrammatical.
Two verbs for two different facts
"They struck up a conversation at the gate, and it turned out they hit it off immediately" — the beginning, then the resulting chemistry, correctly marked with two different verbs.
Want to learn "Strike Up" in depth?
Lyra Practice teaches advanced non-native professionals the nuance of high-value expressions like this one, then has you practice using them in realistic work scenarios.
Start learning for free →"We struck up well" is wrong — strike up needs a noun object. "We hit it off" is the correct way to say the interaction went well.
"We hit it off a conversation about the merger" is wrong — hit it off takes no object. "We struck up a conversation about the merger, and we really hit it off" is correct.
Practice scenarios
Practice using strike up in situations like:
- describing a conversation beginning, before knowing how it will go
- describing how well an interaction is going once it has already started
- using both verbs correctly in one story about meeting someone
Useful practice phrases:
- "We struck up a conversation about..."
- "We really hit it off."
- "We struck up a conversation, and we hit it off right away."
A conversation can be struck up and go badly, and two people can hit it off in an interaction neither of them specifically struck up.
One verb is about the cause, the other is about the outcome — check which one your sentence actually needs.
Lyra Practice helps advanced non-native English professionals learn the nuance of high-value workplace expressions and practice using them in realistic scenarios, so their English sounds natural, precise, and senior at work. Try Lyra Practice.