Depending on where you live and what you do for a living, writing in English may or may not be a requirement. If you live in the United States, England, or other countries whose primary language is English or you have contact with these countries frequently, you will probably be required to write in English.
There is a lot of countries whose official language is not English, however, in such countries you can find a lot of people able to speak English fluently. These are two distinct situations. In other words, English is spoken almost on all countries, even if it is not their official language.
There are many countries whose languages are derived from latin. English, French, Spanish and even German have words that have their derivative roots in Latin.
Students whose Native language isn't English.
No because "whose's" is not a word recognized in the English language. It is either used as "whose" or "whose is".
Anglophones are peoples whose first language is English.
There are 21 countries where Spanish is the official language.
As of 2014, no nation's name starts with X.
ian boothan an English cricket player
Qvale is an Italian car whose spelling begins with the letter "Q" in English and Italian.
Patty potter is a Library Specialist whose native language is English.
If you are speaking as a person whose first language is English, the answer is communication. If you are another 'normal' person the importance needs discussion.