I remember that one of my American friends said,
"Susan, if you pronounce [L] and [R] clearly, your English would be much better!” Even when I learned in a language center, I asked one of my instructors to give me a simple tip for the [R] sound. He said, "Imagine when you are really angry, and say "roar" from just like an angry lion.
It was about 10 years ago. Nowadays, I’ve realized that my strong Korean accent never will disappear no matter what, which means English is my second language and I was exposed to learn how to speak English after the puberty period. Eventually, I came to cherish my Korean accent in English. It’s because I realized that my Korean accent tells my identity to American people as long as I speak English grammatically perfect and my word choice is classy.
The purpose of learning English as international students is not to speak like English native speakers but to communicate with American people or people from different countries. However, it cannot be over emphasized to learn to pronounce correctly in the beginning of learning English, which will affect the entire English learning process.
<how to pronounce the sound of [l] and [r] correctly?>
However, you should make an effort to gain good pronunciation skills as much as you could even though you cannot speak just like English native speakers. Now, I I am able to pronounce [L] and [R] sound much better.
Just practice and practice!!!