You will be given a definition of a task first, then an example. Follow the example to solve a new instance of the task.
In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

what is the first event mentioned?, Context: The Russian Revolution is the series of revolutions in Russia in 1917, which destroyed the Tsarist autocracy and led to the creation of the Soviet Union. Following the abdication of Nicholas II of Russia, the Russian Provisional Government was established. In October 1917, a red faction revolution occurred in which the Red Guard, armed groups of workers and deserting soldiers directed by the Bolshevik Party, seized control of Saint Petersburg (then known as Petrograd) and began an immediate armed takeover of cities and villages throughout the former Russian Empire.
Solution: Russian Revolution
Why? This is a good example, and the Russian Revolution is the first event mentioned.

New input: What are similar?, Context: This change is interesting from a sociolinguistic point of view because it has apparently happened relatively recently, in the 1970s, and was pioneered by older well-educated women from the upper middle classes. The lowering of the diphthongs has long been current in many Dutch dialects, and is comparable to the English Great Vowel Shift, and the diphthongisation of long high vowels in Modern High German, which centuries earlier reached the state now found in Polder Dutch. Stroop theorizes that the lowering of open-mid to open diphthongs is a phonetically "natural" and inevitable development and that Dutch, after having diphthongised the long high vowels like German and English, "should" have lowered the diphthongs like German and English as well.
Solution:
diphthongisation