He was watching her doing it with a _________ look on his face, as if to say that he would not change his mind.

There is an old proverb, “Love me, love my dog.” But there is _________ wisdom in this: “Love me, love my book.”

I am sorry, sir, but that kind of digital camera is no longer _______.

The students are _______ to ride the public bicycles to Mount Tianlong for a spring outing.

Though working outside, he is always      about his aging mother at home.