Do you prefer to do a single project or multiple projects at the same time?

Well, I prefer to do multi-projects at the same time for following reasons:

Firstly, doing multiple projects simultaneously is the most efficient way for me when I face a few works to do at the same time. Because I could distribute the time wisely to every task. Thus, time will be well-planned which means saving time.
What’s more, when I am stuck, I can try another project and probably get some inspiration. When I was a sophomore, I had trouble doing my biological paper. Surprisingly, I was inspired when I was making my historical work.

Corrections 

[ 'multi-projects' -- I wasn't familiar with this specific hyphenation , so I looked it up, apparently 'multi-project' is the correct term for one project with many layers, so using 'multiple projects' is much more clear.]

[ 'saving time' -- 'save' should be in the same tense as other verbs in the sentence.]

[ 'inspiration' -- inspiration is an uncountable thing... you cannot have inspirations at once, but you can have inspirations in more than once instance]

[ 'for the following reasons:' -- use a semicolon when you are about to make a list of things]

[ 'was inspired' -- It's the more proper / grammatically correct way to say "receive inspiration", although 'got inspired' still makes sense, it's just not 100% grammatically correct]

Making your life more meaningful

A saying goes:"the greatest use of life is to spend it for something that will outlast it." It is advisable that we would like to spend our life more meaningfully and not to waste it.
There is no better example than learning. Knowledge is infinite and our life is finite, but we can use our finite life to learn it. Neverthless, making the best use of our life and practising the knowledge what we learn before make it more useful. Socalizing is another example of what l think is meaningful. lt is fun to do some sports , have dinner or present the wedding together with my friends and family members. lf l see a photo or run across a condition like before, l will recall it and feel nice.
After all, making my life more meaningful is easy only to know what to do, why to do and how to do right now.

highlighted sentences - I wasn't entirely sure what you wanted to say..

I was initially confused by 'practising', interestinly enough it's British English.
http://www.future-perfect.co.uk/grammar-tip/is-it-practise-or-practice/ 

Feel free to contact me if you want some explainations,

Chris

Culture & Behavior. (Please help me correct, thank you!)

Culture is defined as a product of long-term human activities, it is invisible and variable but it can be demostrated in different ways. One of the most apparent ways is to be shown through peoples’ behaviors.
When a child was born, they will be taught by their parents about their country's culture. From customs to habits, or even beliefs, they begin to learn how to properly behave in order to become accustomed to their environment. With the different backgrounds, culture can be distinguished through one’s behavior. As for Chinese  or any other Asian children, they were taught to respect their elders and to be modest, while western children learn to treat all the people equally. They may not behave as open as westerners, who have their own perspective of viewing the world, or dare to challege authority. Sometimes, when joining a big party, Asian people would like to talk with people from a similar culture yet western people prefer chatting with different people worldwilde on all kinds of topics, which suggests that Asian people are somewhat conservative as they are influenced by their culture.
On the other hand, peoples’ behavior can also influence culture. We are living in a world where globalization is wide-spreading, many cities are becoming multi-cultural from a growing number of people coming from all over the world and whose behavior is well-mixed with the local culture. There has been a “new culture” formed that is gradually becoming accepted by the public.
Culture and behavior have constantly been impacting each other in such a cyclic pattern.