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.

Example Input: Most light bulbs have either clear or coated glass. The coated glass bulbs have a white powdery substance on the inside called kaolin. Kaolin, or kaolinite, is a white, chalky clay in a very fine powder form, that is blown in and electrostatically deposited on the interior of the bulb. It diffuses the light emitted from the filament, producing a more gentle and evenly distributed light. Manufacturers may add pigments to the kaolin to adjust the characteristics of the final light emitted from the bulb. Kaolin diffused bulbs are used extensively in interior lighting because of their comparatively gentle light. Other kinds of colored bulbs are also made, including the various colors used for "party bulbs", Christmas tree lights and other decorative lighting. These are created by coloring the glass with a dopant; which is often a metal like cobalt (blue) or chromium (green). Neodymium-containing glass is sometimes used to provide a more natural-appearing light.
Example Output: What is the powdery substance in coated glass light bulbs?

Example Input: From 7 September 1940, one year into the war, London was bombed by the Luftwaffe for 57 consecutive nights. More than one million London houses were destroyed or damaged and more than 40,000 civilians were killed, almost half of them in London. Ports and industrial centres outside London were also attacked. The main Atlantic sea port of Liverpool was bombed, causing nearly 4,000 deaths within the Merseyside area during the war. The North Sea port of Hull, a convenient and easily found target or secondary target for bombers unable to locate their primary targets, was subjected to 86 raids in the Hull Blitz during the war, with a conservative estimate of 1,200 civilians killed and 95 percent of its housing stock destroyed or damaged. Other ports including Bristol, Cardiff, Portsmouth, Plymouth, Southampton and Swansea were also bombed, as were the industrial cities of Birmingham, Belfast, Coventry, Glasgow, Manchester and Sheffield. Birmingham and Coventry were chosen because of the Spitfire and tank factories in Birmingham and the many munitions factories in Coventry. The city centre of Coventry was almost destroyed, as was Coventry Cathedral.
Example Output: How many nights did the Luftwaffe bomb London?

Example Input: A regulation of the Rhine was called for, with an upper canal near Diepoldsau and a lower canal at Fußach, in order to counteract the constant flooding and strong sedimentation in the western Rhine Delta. The Dornbirner Ach had to be diverted, too, and it now flows parallel to the canalized Rhine into the lake. Its water has a darker color than the Rhine; the latter's lighter suspended load comes from higher up the mountains. It is expected that the continuous input of sediment into the lake will silt up the lake. This has already happened to the former Lake Tuggenersee.
Example Output:
Where is the upper canal regulation of the Rhine?