In this task, you're given an article and an answer. Your task is to generate the fill-in-the-blank question for this answer based on the given article. The blanks are always at the end of the question, and can be filled with more than one word or phrase.
--------
Question: Article: There have been many great inventions that changed the way we live.The first great invention was one that is still very important today--the wheel.This made it easier to carry heavy things and to travel long distances.For hundreds of years after that there were few inventions that had as much effect as the wheel.Then in the early 1800's the world started to change.There was little unknown land left in the world.People did not have to explore much anymore.They began to work instead to make life better.In the second half of the 19th century many great inventions were made.Among them were the camera, the electric light and the radio.These all became a big part of our life today. The first part of the 20th century saw more great inventions.The helicopter in 1909.Movies with sound in 1926.The computer in 1928.And jet planes in 1930.This was also a time when a new material was first made.Nylon came out in 1935.It changed the kind of clothes people wear.The middle part of the 20th century brought new ways to help people get over disease. _ worked very well.They made people healthier and let them live longer lives.By the 1960's most people could expect to live to be at least 60.By this time most people had a very good life. Of course new inventions continued to be made.But man now had a desire to explore again.The world was known to man but the stars were not.Man began looking for ways to go into space.Russia made the first step.Then the United States took a step.Since then other countries, including China and Japan, have made their steps into space.In 1969 man took his biggest step away from the earth.Americans first walked on the moon.This is certainly just a beginning though. New inventions will someday allow us to do things we have never yet dreamed of.
Answer: 1850

Answer: Camera was invented after _ .

Question: Article: Sitting across from a German couple and a Chinese mother and child, we were waiting at the Guilin airport for our delayed flight to Shanghai In this last week of our travel-study tour, my husband and I were savoring this mini-break by reading. While surrounded by languages I couldn't understand, it was an American accent that my attention was pulled from my book It also pulled the attention of three rows of people seated around us as the American barked, "Coming through! Coming through!" At the same time, an oversized man pulling an oversized carry-on turned down our row. His wheeled bag caught the foot of the German maa Turning to see what snagged his luggage ,the American bellower yanked his bag hard enough that it crossed over the man's feet It was then that my horror struck. There was no "I'm sorry; no "Excuse me" 5 no "Pardon me" coming from this countryman of mine. While this wasn't the first or last incident where I sighted impolite, ill-mannered, rude Americans in China, each produced similar feelings. First, I was embarrassed that someone from my country was creating a negative impression of Americans. My second reaction was a desire to apologize. I wanted to explain to the ChiiKse woman and her child, the German couple next to her, and everyone nearby that this was not typical American behavior. I wanted them to know "we" were all not like that I never got to explain, or to apologize. Language differences made that option impossible, and rational thinking made it inappropriate. But there turned out not to be a need The German man caught my eye and with a bit of head-shaking, smiling and eye rolling* which I returned, it was clear he knew we were Americans and was expressing that there was "no need" to apologize for "universal idiot behavior".
Answer: uneasy and sorry

Answer: Every time the author saw some Americans' bad behavior in China, she always felt _

Question: Article: With an overwhelming variety of educational toys and learning tools in the market, you really wonder if these educational products are really beneficial to children. There have been many educational DVDs in the market that promise to stimulate a child's learning and enhance his or her cognitive skills. Parents feel good about buying these products for their children. After all, these educational tools try to do a parent's job of participating in the child's education, especially when the parent can't be present due to his or her busy schedule. Moreover, children seem to love these DVDs that contain pictures, words, and loads of stories. Some DVDs contain fun, sing-along songs or read-aloud words to help the children learn different concepts and words. Although these are fun for the parents and the children, the question that needs to be asked is whether these DVDs are actually beneficial to the child, as they claim to be. Although parents expected "educational" products to give their child some educational advantage, research has shown otherwise. Researchers in a recent study concluded that there was indeed no difference between the language and cognitive ability of the infants who were repeatedly exposed to educational DVDs and those who were not exposed to the DVDs. In fact, contrary to expectations, it was found that babies who were exposed to the DVDs at an earlier age had lower overall language scores at a later age. This suggested a damaging effect of such DVDs on younger children. For several years the American Academy of Pediatrics has recommended that toddlers under age of 24 months or 2 years should not watch videos or television. However, there are many parents who believe these DVDs really help in stimulating the child and keep him or her entertained. While it may work as a great babysitter, it is important to limit activities like video games, computer games, DVDs or TV programs. To promote their children's development and cognitive skills, parents are advised to spend time with their children and increase interaction with them. For example, if you want to enhance language development, converse with the child, listen, and respond to whatever the child is trying to communicate. Children learn more by interacting with parents, rather than by watching DVDs.
Answer: these DVDs are effective in improving children' s cognitive skills

Answer:
Many parents love to buy educational DVDs for their children actually because _ .