Our boss is very ________，so we have to arrive on time，or we would be fined.

This advertisement is a/an______ example of their marketing strategy

Cycling is highly _____ to people’s health and the environment.

In the new curriculum, some courses are        , while others are optional for middle school students.

 Successful people have some good qualities and above all, they are never ________ a simple life so they keep fighting until they become top ones.