البحث:

الكتاب مليء بالأخطاء والأصح هو الذي تقوله .

I think it is correct.

I agree with those who say happier .
It s really long adjective because it has two syllables, but the structure says that a two syllable adjective which ends with y deals as short comparative forms.

Hay
I made three paper of new words. Every paper contains 100 words.
Might they be beneficial for you and your students.
http://www.saudienglish.net/vb/uploaded/26550_01176667379.zip

Thaaaaaaaaaanks for Great Efforts.