“Radiance,” “strike a deal,” “gorgeous” “ecosystem.” In my 40 years of teaching academic ESL, I’ve probably seen these word in a reading passage at most only once or twice. And I’ve never seen a student use them in a writing task. And yet, these words were included in several vocabulary exercises in a textbook, and students were asked to write sentences with them. Because the words were in a reading passage, the author of the textbook, for some reason, decided that these were important words for students to study and try to internalize.
I think most of us would agree that spending time on words so rarely used as “radiance” or “strike a deal” is probably not the best use of students’ precious time and mental energy if our true goal is to help them develop their reading skills. At the same time, many of us who have studied a foreign language would agree that reading comprehension is enhanced by knowledge of a lot of vocabulary words.
At this point, two questions come to mind: (1) How do learners increase their vocabulary, and (2) which vocabulary words would perhaps be beneficial to study through exercises?
I discuss this posting in this video: 
Common Sense Teaching ESL 