"Th" and good English pronunciation

There are three levels of English pronunciation:

People don’t understand what you say.

People have to concentrate to understand you.

You have clear pronunciation and are easily understood.

I think that most people worry about how they sound when speaking a new language and I want to help reduce that anxiety for English learners.
I recommend listening to sound recordings whenever you’re in doubt and repeat, repeat, repeat. I like this online dictionary because it provides both the American and British English pronunciation of words. (The example word is thought.)
A lot of people have trouble with the ‘th’ sound in English words. Correct pronunciation requires placing the tip of your tongue between your teeth and then forcing air over your tongue and under your top teeth. Try it! Also, it’s important to know that there are two sounds for ‘th’: voiced and unvoiced.

Voiced: your throat vibrates as you say it (there, then, this, weather, northern).

Unvoiced: there is only the silent hiss of air as you say it (thought, south, with, math, thin).

Listen to the difference and practice it for yourself!