This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
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Question: Meetings for worship and study are held at Kingdom Halls, which are typically functional in character, and do not contain religious symbols. Witnesses are assigned to a congregation in whose "territory" they usually reside and attend weekly services they refer to as "meetings" as scheduled by congregation elders. The meetings are largely devoted to study of Watch Tower Society literature and the Bible. The format of the meetings is established by the religion's headquarters, and the subject matter for most meetings is the same worldwide. Congregations meet for two sessions each week comprising five distinct meetings that total about three-and-a-half hours, typically gathering mid-week (three meetings) and on the weekend (two meetings). Prior to 2009, congregations met three times each week; these meetings were condensed, with the intention that members dedicate an evening for "family worship". Gatherings are opened and closed with kingdom songs (hymns) and brief prayers. Twice each year, Witnesses from a number of congregations that form a "circuit" gather for a one-day assembly. Larger groups of congregations meet once a year for a three-day "regional convention", usually at rented stadiums or auditoriums. Their most important and solemn event is the commemoration of the "Lord's Evening Meal", or "Memorial of Christ's Death" on the date of the Jewish Passover.

Answer: How often did Jehovah Witnesses congregations meet prior to 2009?


Question: In Ukraine, Lviv and Kiev celebrated Ukrainian Independence Day on January 22, 1989. Thousands gathered in Lviv for an unauthorized moleben (religious service) in front of St. George's Cathedral. In Kiev, 60 activists met in a Kiev apartment to commemorate the proclamation of the Ukrainian People's Republic in 1918. On February 11–12, 1989, the Ukrainian Language Society held its founding congress. On February 15, 1989, the formation of the Initiative Committee for the Renewal of the Ukrainian Autocephalous Orthodox Church was announced. The program and statutes of the movement were proposed by the Writers Association of Ukraine and were published in the journal Literaturna Ukraina on February 16, 1989. The organization heralded Ukrainian dissidents such as Vyacheslav Chornovil.

Answer: What is commemorated on January 22 in Ukraine?


Question: Elevator doors protect riders from falling into the shaft. The most common configuration is to have two panels that meet in the middle, and slide open laterally. In a cascading telescopic configuration (potentially allowing wider entryways within limited space), the doors roll on independent tracks so that while open, they are tucked behind one another, and while closed, they form cascading layers on one side. This can be configured so that two sets of such cascading doors operate like the center opening doors described above, allowing for a very wide elevator cab. In less expensive installations the elevator can also use one large "slab" door: a single panel door the width of the doorway that opens to the left or right laterally. Some buildings have elevators with the single door on the shaft way, and double cascading doors on the cab.

Answer:
How do most elevator doors work?