Definitely use the or a

Definitely use the or a Definitely use the or a Definitely use the or a By Michael When to use the indefinite article a and when to use the definite article the depends mostly on how specific you want to be. During a wedding ceremony the groom would say, Give me the ring! The wedding ring! because he must have a particular ring, while a carpenter would say, Hand me a nail because he doesnt care which nail in the box he uses. Usually the bigger problem is not whether to use a definite or indefinite article, but whether to use an article at all. So many choices! When do you use a? When do you use an? When do you use the? But relax. Well guide the way. We already talked about when to use a when to use an in the article Give me an A: a vs. an, but well give you a few more examples here. A: you use this when youre not necessarily referring to a specific thing (such as a nail, any nail). Its called an indefinite article, because youre not being definite or particular. There are many nails in this big world. She owns a cat. I work on a golf course. An: its used just like a, but when preceding a vowel sound. It probably comes from Old German, on which Old English was based. My theory is that the use of an survives after all these centuries because it sounds better before vowels. Saying, I want a apple sounds odd, compared to, I want an apple. For the same reason, the fake French sentence, Anne, on en a un, sounds even more odd. May I borrow an egg? He is an arrogant critic. The: youre talking about a definite item, which is why the is called a definite article. Of course it only makes sense if both you and your listeners know which item you mean. If I commanded you, Give me the money, you would rightfully ask, What money? I dont owe you any money. The house on that corner once belonged to Charles Dickens. The weather is very pleasant today. You can use the the second time you refer to something, even if you used an the first time. We know what youre referring to, because you just told us. You can do this, but I wouldnt recommend it. Read these examples repeating the noun might sound monotonous. We visited a palace on our vacation. The palace was built in 1546. We also went to a concert. The concert was too loud for me. When it comes to geography, you dont use the before the names of most nations, provinces, states,lakes or islands. But there are many exceptions: the United States, the Ukraine, or the Congo. On the other hand, the Ukrainians and Congolese people Ive met say, Ukraine and Congo, so go figure. If the name refers to plural items, such as the United States, or the Maldives, you would use the definite article. You would do the same for rivers and oceans, such as the Amazon, the Nile, and the Caspian Sea. Bays need the definite article. He moved to Nepal near Mount Everest. They spent their honeymoon in eastern Maine, on Penobscot Bay. Unlike some languages such as French and Spanish, English sometimes does not use any article at all. You dont need one when making a general statement, or when talking about meals and transportation. I prefer folk music. She hates making noodles. She eats breakfast at home. She traveled to college by train. British writers dont use an article for some places that Americans would. British: I go to university. American: I go to college. American: I transfered to the university last year. British: I felt so ill that I went to hospital. American: I got so sick I had to go to the hospital. Some rules apply all the time. Some rules apply only in certain situations, and only experience and reading can help you get them all right. And some rules apply only in certain situations in certain cultures: British and American English is sometimes different, as you may have learned by now. Want to improve your English in five minutes a day? Get a subscription and start receiving our writing tips and exercises daily! Keep learning! Browse the Grammar category, check our popular posts, or choose a related post below:Cost-Effective vs. Cost-EfficientStory Writing 10145 Idioms About the Number One

The History and Invention of the Jet Engine

The History and Invention of the Jet Engine Although the invention of the jet engine can be traced back to the aeolipile made around 150 B.C., Dr. Hans von Ohain and Sir Frank Whittle are both recognized as being the co-inventors of the jet engine as we know it today, even though each worked separately and knew nothing of the others work. Jet propulsion is defined simply as any forward movement caused by the backward ejection of a high-speed jet of gas or liquid. In the case of air travel and engines, jet propulsion means that the machine itself is powered by jet fuel. While Von Ohain is considered the designer of the first operational turbojet engine, Whittle was first to register a patent for his schematics of a prototype, in 1930. Von Ohain obtained a patent for his prototype in 1936, and his jet was the first to fly in 1939. Whittles took off for the first time in 1941. While von Ohain and Whittle may be the acknowledged fathers of modern jet engines, many grandfathers came before them, guiding them as they paved the way for the jet engines of today. Early Jet Propulsion Concepts The aeolipile  of 150 BCE was created as a curiosity and never used for any practical mechanical purpose. In fact, it wouldnt be until the invention of the fireworks rocket in the 13th century by Chinese artists that a practical use for jet propulsion was first implemented. In 1633, Ottoman Lagari Hasan Çelebi used a cone-shaped rocket powered by jet propulsion to fly up into the air and a set of wings to glide it back to a successful landing. However, because rockets are inefficient at low speeds for general aviation, this use of jet propulsion was essentially a one-time stunt. In any event, his effort was rewarded with a position in the Ottoman Army. Between the 1600s and World War II, many scientists experimented with hybrid engines to propel aircraft. Many used one of the piston engines forms- including air-cooled and liquid-cooled inline and rotary and static radial engines- as the power source for aircraft. Sir Frank Whittles Turbojet Concept Sir Frank Whittle was an English aviation engineer and pilot who joined the Royal Air Force as an apprentice, later becoming a test pilot in 1931. Whittle was only 22 when he first thought to use a gas turbine engine to power an airplane. The young officer tried unsuccessfully to obtain official support for the study and development of his ideas but was ultimately forced to pursue his research on his own initiative. He received his first patent on turbojet propulsion in January 1930. Armed with this patent, Whittle again sought funding to develop a prototype; this time successfully. He began construction of his first engine in 1935 a single-stage centrifugal compressor coupled to a single-stage turbine. What was meant to be only a laboratory test rig was successfully bench-tested in April 1937, effectively demonstrating the feasibility of the turbojet concept. Power Jets Ltd. the firm with which Whittle was associated received a contract for a Whittle engine known as the W1 on July 7, 1939. In February 1940, the Gloster Aircraft Company was chosen to develop the Pioneer, the small engine aircraft the W1 engine was earmarked to power; the historic first flight of the Pioneer took place on May 15, 1941. The modern turbojet engine used today in many British and American aircraft is based on the prototype invented by Whittle. Dr. Hans von Ohains Continuous Cycle Combustion Concept Hans von Ohain was a German airplane designer who obtained his doctorate in physics at the University of Gà ¶ttingen in Germany, later becoming the junior assistant to Hugo Von Pohl, director of the Physical Institute at the university. At the time, von Ohain was investigating a new type of aircraft engine that did not require a propeller. Only 22 years old when he first conceived the idea of a continuous cycle combustion engine in 1933, von Ohain patented a jet propulsion engine design in 1934 very similar in concept to that of Sir Whittle, but different in internal arrangement. Upon the mutual recommendation of Hugo von Pohl, Von Ohain joined German aircraft builder Ernst Heinkel, at the time seeking assistance in new airplane propulsion designs, in 1936. He continued development of his jet propulsion concepts, successfully bench-testing one of his engines  in September 1937. Heinkel designed and constructed a small aircraft known as the Heinkel He178, to serve as a testbed for this new propulsion system, which flew for the first time on August 27, 1939. Von Ohain went on to develop a second, improved jet engine known as  the He S.8A, which was first flown on April 2, 1941.