Teaching phonetics

English is still the universal language

Estimates vary about how many people speak English worldwide, but some believe English-speakers are likely to number in the billions. English crosses cultures, countries and industries. It’s often used as a ‘common tongue’ if neither person is a native speaker. This means teaching people English can be truly rewarding: students of English have many new opportunities and doors open to them thanks to their skills.

The internet is English

About half of homepages on the internet are in English and as of 2016 the English edition of Wikipedia contains the most articles. If you want full use of the web (without lots of translation work), English is key. Plus internet use is now an important and necessary part of many jobs, with increased remote-working (and much of daily life). Helping people learn English means helping them take full advantage of the power of the web. You can even teach English online as opposed to in-person classes!
With the advancement of information technology, the teaching of a foreign language changes fast, not just for the tools we have at our disposal, but also for our perception of it.
Teaching English follows a more and more utilitarian path (people learn English mostly for job-related purposes) yet as educators, I think we should pursue a higher scope: teaching values to our students and help them to become better people, especially when we work with juniors.
HOW TO IMPROVE LISTENING SKILLS IN ENGLISH
Along with reading, writing, and speaking, listening is one of the key skills you need to master if you want to master the English language. However, it is also a skill that many learners struggle with.

What makes listening so difficult:

In comparison with reading, there are a few things that make listening harder to master. To understand speech and recordings in English, it is not enough to have a large vocabulary and good grammar. You need to know correct English pronunciation, but, unfortunately, that is not enough either. 

Each speaker brings their unique peculiarities to speaking English: their accent, how clearly they speak, how fast they speak. If you have never heard a native speaker talk before, understanding them can be really hard even if your general level of English proficiency is quite high. 

The language itself does not make it any easier. English has lots of words that differ a lot in spelling and in pronunciation.