Keep in mind that the actual pronunciation of a word often changes when used in everyday conversation (rather than in isolation, as found here).If you encounter a word you don't know, then use a dictionary (an English-English is recommended) to find the definition for each.
As you learn the vocabulary, try to use it in other situations.
Learning English as a second or foreign language (ESL / EFL) takes time, and building your vocabulary is an important key to improving your communication skills.
Thus, students need to learn how to understand and use vocabulary in everyday situations.
A good dictionary will also give you a sample sentence so you can see how the word is used in context.
The lessons are not intended to provide all of the definitions for the words; rather, students should look up the words as a means of developing their study and dictionary skills.