Thereby means as a result of this, by doing this: it shows the effect of the action you've just named. The museum introduced timed tickets, thereby reducing queues: the tickets cut the queues. It's formal and looks good in reports and IELTS essays. In conversation, just say so or and that way.
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action, thereby + verb-ing; subject + verb + and thereby + verb
- The museum introduced timed tickets, thereby reducing queues at the entrance.
- You can switch off notifications and thereby avoid interruptions.
- The new route bypasses the town centre, thereby shortening the journey.
What changed
First versionThe team shared one calendar, thereby reduce scheduling errors.
RevisionThe team shared one calendar, thereby reducing scheduling errors.
The result feels like an ordinary action, so a plain verb seems natural: thereby reduce. But after a comma, thereby starts an -ing phrase: thereby reducing scheduling errors. If you want a normal verb, you need and: and thereby reduced.
Therefore means for that reason and introduces a conclusion: The room was empty; therefore, we left. Thereby shows the result of a specific action: We closed the window, thereby reducing the noise. Quick check: if by doing this fits, you need thereby.
Your turn
We combined the two deliveries, thereby ___ packaging waste.
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reducing — After the comma comes thereby + -ing, so reducing. Reduced would need and: and thereby reduced.
Describe one change in your studies or work and what it achieved straight away, linking the two parts with thereby.
We labelled the shelves, thereby making the tools easier to find.
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