If you go straight on will you be driving on a major road?

In the photo on the right there is sign D-1 "priority road", and arrows on the roadway show that from your right lane you can go straight on or right, and from the left lane - straight on or left. Sign D-1 without a plate means that the priority road goes straight on, so if you go straight, you will still be on it. The answer is: yes.

The Regulation on road signs and signals states that sign D-1 means the start or continuation of a priority road; if the priority road turned, there would be plate T-6a under the sign showing its real course. Vehicles from minor roads must give way to you, but you do not assume that everyone will do it - you drive through the junction carefully.

Legal basis: § 43 para. 1 and 2 of the Regulation on road signs and signals