SOPs are not mandatory, but are extremely beneficial for securing visa. You are going there as a student. So, always make sure that your whole focal point is studying and then returning back (and e.g. help with your family business, work jobs in your country, etc). Do not state that you want to stay there after studying. Don't use templates. They are not going to score your SOPs, so just write in your own words. Whatever line you are choosing for your studies, explain why you have chosen that line. Add the following points too in your SOP:
Part 1: Introduce yourself, your interests and motivations. Tell them what you’re interested in, and perhaps, what sparked your desire for graduate study. This should be short and to the point; don’t spend a great deal of time on autobiography.
Part 2: Summarize your undergraduate and previous graduate career.
a) Research you conducted. Indicate with whom, the title of the project, what your responsibilities were, and the outcome. Write technically, or in the style of your discipline. Professors are the people who read these statements.
b) Important paper or thesis project you completed, as well as anything scholarly beyond your curricular requirements.
c) Work experience, especially if you had any kind of responsibility for testing, designing, researching or interning in an area similar to what you wish to study in graduate school.
Part 3: Discuss the relevance of your recent and current activities
If you graduated and worked prior to returning to grad school, indicate what you’ve been doing: company or non-profit, your work/design team, responsibilities, what you learned. You can also indicate here how this helped you focus your graduate studies.
Part 4: Elaborate on your academic interests
Here you indicate what you would like to study in graduate school in enough detail to convince the faculty that you understand the scope of research in their discipline, and are engaged with current research themes.
a) Indicate the area of your interests. Ideally, pose a question, define a problem, or indicate a theme that you would like to address, and questions that arise from contemporary research. This should be an ample paragraph!
b) Look on the web for information about departments you’re interested in, including professors and their research. Are there professors whose research interests parallel yours? If so, indicate this. Check the specific program; many may require you to name a professor or professors with whom you might work.
c) End your statement in a positive manner, indicating your excitement and readiness for the challenges ahead of you.
Emphasize everything from a positive perspective and write in an active, not a passive voice. Demonstrate everything by example; don’t say directly that you’re a persistent person, show it. If there is something important that happened to you that affected your grades, such as poverty, illness, or excessive work, state it. Write it affirmatively, showing your perseverance despite obstacles. You can elaborate more in your personal statement. Make sure everything is linked with continuity and focus. Unless the specific program says otherwise, be concise; an ideal essay should say everything it needs to with brevity. Approximately 500 to 1000 well-selected words (1-2 single space pages in 12 point font) is better than more words with less clarity and poor organization.
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