Not ______ openly may make one’s point confusing, while careless words are ______ to hurt others’ feelings.

(2013·银川一中二模)—Are you pleased with what he has done?—Not a bit. It couldn’t be________.

___ to 100℃, water will boil.

It’s really a great pity that the greatwriter died ____ his works unfinished.

Lily and her sister look the same. I can’t tell one from_______.