Kono hon wa kanji ga ookute muzukashii desu.

This book has many kanji and is difficult.

Nihongo wa eigo yori muzukashii to omoimasu.

I think Japanese is more difficult than English.

Shukudai ga muzukashikattara, sensei ni kiite kudasai.

If the homework is difficult, please ask the teacher.

Senshuu no shiken wa muzukashii mondai ga ookatta desu.

There were many difficult questions on last week's exam.

Kyou no tesuto wa amari muzukashikunakatta desu.

Today's test was not very difficult.

Ashita made ni zenbu oboeru no wa muzukashii desu.

It is difficult to memorize everything by tomorrow.