is this sentence OK？ G

are circular or to be circular for the sake of simplicity, we have assumed all (the) pneumatic channels are circular/ to be circular.

at very first time; at the very first time; at very the first time ; which is correct ? In 2014, Lauder research group at Harvard University, for very the first time, successfully manufactured flexible bio-mimetic shark skins

corresponds or corresponding The surface morphology, usually corresponds/corresponding to the mechanical instabilities, could be determined by the theory of solid mechanics.

Rather than DO or DOing A well-known application of dimpled drag-reducing surface is golf ball, which have about 250-400 dimples on the surface rather than have/having a smooth surface. Could I use 'have' or 'having' in the sentense? Thanks for your time.

IELTS Writing task 2. Why children are unhappy? In some countries, many children are unhappy. What are the reasons? What can parents and schools do to solve this problem? Over the past 20 years, socialists have been increasingly aware that many children appear to be unhappy with their life in some countries. In this essay, I will take my country-China for an example to explain why this situation happens and which measures should parents and schools take to deal with this issue. An initial reason for the unhappiness for children is the much heavy studying burden. Children in developing countries like China are experiencing increasingly high exam stress in order to enter a college since China’s educational resources are still in shortage. A lot of children have to attend exam training courses on weekends, which occupy their leisure time. Another possible reason is the case that many children in urban areas feel lonely. They usually live in separate communities and thus have little time to spend together after school. Parental company plays an major role in children’s happiness. Parents should spare ample time to spend with their kids, paying heed to what they are saying but without judging them. Adults should also teach their kids about how to build friendships with their peers. In addition, schools should respect children’s privacy, for example, tutors do not rank their students by exam results, which would have a negative effect on students’ confidence. Schools or educators could also organize high quality class activities regularly to boost the friendships among classmates. In conclusion, heavy exam stress and the lack of friends are two main reasons why children feel unhappy. To solve this problem, I personally believe that parents should pay much more attention to their kids and work together with schools to assist children build friendships with peers.

IELTS writing task 2. New technologies or free education? Some people think that governments in developing countries should introduce new technologies   to people  in order to improve the quality of life, while others believe that in order to achieve that  governments should  offer free education for all. Discuss both these views and give your own opinion.  It is a crucial social issue in terms of how to improve the life quality of people who are living in developing countries. Some scientists suggest that governments should import new technologies while some educationalists reckon that providing free education for the public should be a better way. I personally tend to agree that both advice sounds reasonable but the former one seems to be more viable and practical. People’s daily life invariably benefits from new technologies. For example, governments could import modern public transport systems like urban rail transit and rapid bus transit to provide cheaper and more comfortable seats for city commuters, and thus tackle traffic jams in the urban area. For those who are living in rural area, the local communities and governments may introduce modern agricultural techniques such as fertilizers and irrigation systems to help farmers produce much more crops and grains. This would contribute to reducing the living cost in the rural area. In addition, new clean and sustainable energy technologies like nuclear energy and solar energy should be adopted to reduce the consumption of coal and petroleum, serving to solve the growingly severe air pollution problems in developing countries. Providing free education for the public would also help. Expectedly, an individual who has been well trained and holds a higher degree would have more chance to find a better job. However, given the limited budget in developing countries, this policy seems to be less realistic. In conclusion, although free education for the public seems to be useful to improve the literacy level in developing countries, innoviative technologies could directly prompt the developing in cities and rural countries, which would increase the life quality of people.(281 words)

Ielts writing task 2. traffic problems In some countries, private car drivers have to pay congestion tax for traffic problems. Some people think this will be helpful while others think there are better ways to solve traffic problems. Discuss both views and give your opinion. Over the past 50 years, people have been increasingly aware that some actions must be taken to tackle the growingly severe traffic jams. Some socialists and economists suggest that government should force private vehicle owners to pay an extra tax for traffic congestion. However, I tend to agree that this policy might not be able to solve the traffic problems radically, and there exist other more practical and viable solutions. Initially, the congestion tax policy is helpful to reduce the traffic jams. It serves to reduce the desire of car owners to use their cars and thus would decrease the number of vehicles on the road. However, it seems to be less valid to limit the car using of the rich individuals, who would rather pay a little money than waste their time on the road. A possible solution to the urban traffic jams is to develop the public transport systems such as urban rail transit and bus rapid transit. Since the traffic problem is relatively serious at rush hours when workers travel between home to work places, supposing that urban metros serves to provide cheaper and more comfortable seats for commuters, the traffic congestion is predicted to be relieved then. Another viable approach to ease the traffic pressure is to encourage citizens to take bicycles. To be specific, government could separate bikeways for bicyclists from traditional vehicle paths. In addition, traffic signals for bicycles should be introduced and plenty bicycle parking racks should be constructed. Overall, forcing private car drivers to pay an extra congestion tax could be useful to relieve the traffic pressure to some extent. However, more practical and viable solutions to this problem should be the development of public transport systems and alternative traveling ways.

Ielts writting People change their careers and places of residence several times during their life. In the past, people usually worked for only one company during their whole life; these days, it is not uncommon for individuals to change jobs or even transfer from a country to another. Although some socialists concern that transforming jobs frequently may cause a negative effect on individuals’ career. In this essay, I would argue that experiencing several professions is overall positive for both individuals and corporations. An obvious advantage for individuals is that changing a job provide people with an opportunity to experience different careers and contact various cultures. For example, my PhD supervisor is a French person who works for my university at the moment. After he obtained his doctor degree ten years ago in France, he did research in various academic institutions from several countries, including the USA, the UK, and German. Now he is a internationally famous scientist and he always tells us that it is the rich research experiences open his eyes and broaden his horizon and eventually enable him to obtain the great success in his career. It is undeniable that working at various countries would encourage individuals to become an international citizen. Another positive effect is in terms of increasingly competitive commercial environment. Leaving current employer and finding a new corporation always means that individuals could acquire new skills and enlarge the social networks. On the other hand, corporations could also benefit from new ideas and new enthusiasms brought by new comers. There also exists a drawback if one person transforms vocations too much frequently as employers would doubt employees’ reliability and loyalty which are pretty crucial factors for ones’ career development. In short, I personally reckon that transforming jobs and working at various countries or places has an overall positive effect on individuals’ career development. However, it is worth noting that do not change your employers too often.(310words)