ernstige
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Summary
The Dutch translation for “serious (long form)” is ernstige.See also
Examples of "serious" in use
There are 2 examples of the Dutch word for "serious" being used:Practice Lesson
Lesson
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Lesson words
Acknowledgements
Image source
https://pixabay.com/th/photos/%E0%B8%AB%E0%B8%A1%E0%B8%94%E0%B8%AB%E0%B8%A7%E0%B8%B1%E0%B8%87-%E0%B8%84%E0%B8%B4%E0%B8%94%E0%B8%A7%E0%B9%88%E0%B8%B2-%E0%B9%80%E0%B8%84%E0%B8%A3%E0%B8%B5%E0%B8%A2%E0%B8%94-%E0%B8%9B%E0%B8%A7%E0%B8%94%E0%B8%AB%E0%B8%B1%E0%B8%A7-%E0%B8%95%E0%B8%81%E0%B8%95%E0%B9%88%E0%B8%B3-5011953/