This was the answer to a previous question I helped someone with, so I am just copy-pasting it here since it fits all the criteria of your question:
English should be America's national language because the population percentage of people who do not speak English at home are at 19.7 percent, leaving 80.3 percent to full English speakers. Even though Europeans came later, its populace of Europeans grew faster and larger than had it been elsewhere. In conclusion, the English language should be declared as the number one language because it is spoken more throughout the country, and it's developed new accents in interior states.
Here are some transitional words and phrases to help you in the future: likewise, however, although, on the contrary, in view of, in detail (for example), another key point, etc. You can find more transitions on http://www.smart-words.org/linking-words/transition-words.html. Good luck!
