FIX: Mitranslation of the footnote for Exercise 1.31
Unify Japanese word for lambda caliculous
1. Find the way to use Japanese in math mode (!!!) Use \mbox{}
2. Fix: ejsicp.tex doesn't have jnewterm, so remove it
3. lambda calculous (Enzan -> Keisan)
Delete unnecessary English text
Remove unnecessary English text from 2.4.3
See commit history of tex files for details