Four-Letter Words

This game has nothing to do with offensive words.I play it just for fun and the students like it a lot. You will be amazed to see how many different words can be generated from a single word!
1.-The teacher writes a four-letter word (not a bad word but word made up four letters) on the board.
For example:
The teacher writes on the board: TIME
2.-Students will take turns generating words from the first one.The idea is to change only one letter but generate a miningful word.
TEACHER.-TIME
STUDENT1.-DIME
3.-Any letter can be change.Only one at a time, but not on the same place consecutively.Example:
TEACHER.- TIME
STUDENT1.- DIME
STUDENT2.- LIME (Wrong you should change any other letter but not on the same place consecutively).
TEACHER.- TIME
STUDENT1.- DIME
STUDENT2.- DOME
STUDENT3.- COME
STUDENT4.- CAME
STUDENT5.- CANE
Etc.
Etc.
The teacher has to limit the time the students take to write the words (may be 20 seconds). The students score a point for each meaningful word they write. If a student takes too much time he loses his turn. Finally the student who makes more points is the winner.