Welcome to Wikipedia, Thuhangtrinh! Thank you for coming here. I have been editing Wikipedia for eight years, so if you have any questions feel free to leave me a message on my talk page. You can also check out Wikipedia:Questions or type ((help me)) at the bottom of this page. Here are some tips that you might find helpful:
You can add links to other articles by putting the article name in [[double square brackets]]
You can add pictures from Wikimedia Commons by putting them in [[double square brackets with|thumb for thumbnail|Left right or centre so it knows where to go|a meaningful caption]]
Example [[File:Meerkat stare.jpg|thumb|right|Please pay attention, just like this meerkat]]
Please DO NOT use anything from Google Images, due to copyright issues. Only Wikimedia Commons images can be freely used.
You can add headings by putting them in ==double square equal signs== and ===subheadings are similar===
This then means that you can edit one section of an article while someone else edits another part of the same page.
To add a reference first check that ((reflist)) is at the end of the article.
Then add your reference <ref>[The webpage you are citing a description & retrieved today's date]</ref>
If you find unreferenced information on Wikipedia that you consider dubious or unlikely, first try to reference it with a search on the internet. If you know it is wrong correct it, if you can't find a source then adding ((fact)) adds the (in)famous "citation needed". If you come back in a week or two and find that no one has referenced the information, feel free to remove it.