If you learn English as a second language then you come to learn the basic first and practice to be able to use them continually. You might focus on learning the grammar and other points in learning English rather than having much vocabulary. Having a wide range of vocabulary is good but it is not easy so you may have a limited knowledge. But you can come to increase it as time passes by. Even those who speak English can sometimes forget what terms to use alternatively.
You can read the sixteen list of words above that is labeled as boring and you can see in each of it twelve words that you can use alternatively. If you practice using them you can be able to sound excellent and you may find that your confidence level is increasing. Speaking other language is very nice as you can feel something when you do it through search engine. The English language is one that is used universally even in trade so many come to learn it.
If you already did also then improving is the one left. You can improve your vocabulary just like the ones above or the pronunciation skills. Sometimes if a person is speaking in English you can know that it is not his native language as the accent is different. Even if you will not adapt to the accent but if you can pronounce it properly then it is better. There are many apps these days that you can freely download.