I use drills for two reasons:
1. Pronunciation.
2. To clarify the meaning of a word. I consider it is better than giving the definition or a synonym to the S since this technique is inductive and; thefore, meaningful for them.
e.g: S: Teacher what does "large" mean?
T: Ok, repeat after me: the elephant is large, the whale is large, the ocean is large, etc. You may use body language as well with this technique in order to foster comprehension of the word.