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Without.

Yes, you can read Russian books on this device. The Kindle supports various file formats, including AZW, MOBI, and PDF, which can contain Cyrillic text. However, the device's interface language options may not include Russian, but you can still read books in Russian by loading them onto the device. Additionally, you can use a foreign language dictionary to help with translations while reading.

The Kindle Paperwhite Signature Edition is ad-free. If you buy the standard model, it will show ads on the lock screen unless you pay an extra $20 to remove the ads. Since the Signature model is mentioned in your question, it is ad-free.

The Kindle Paperwhite Signature Edition does not normally contain adverts, as it is usually offered as an ad-free version. However, if you have purchased a model with adverts, the adverts will appear on the lock screen and home screen, not while you are reading. You can remove the adverts afterwards by paying a fee to Amazon or disconnecting the device from your Amazon account.

Ohne. Sans. Without.

Yes, you can.