Besides all the obvious reasons why you should get yourself some basic Vietnamese before coming, learning Vietnamese helps you experience the culture differently from regular tourists. You will be able to live like a true local, even just for a short time. Vietnamese people are very generous and welcoming.

How difficult is it to learn Vietnamese?

Vietnamese. Why it's hard: Vietnamese is a tonal language with six different tones that dictate the meaning of a word. The high number of vowel sounds also prove difficult for English speakers to nail down.

How long does it take to learn Vietnamese fluently?

According to the US's Foreign Service Institute (FSI), for a native English speaker to be proficient in Vietnamese, it would take approximately 1,110 class hours. This means that if you dedicate 1 hour every day, 7 days a week to learn Vietnamese, you will be proficient after 40 months (~3 years).