Personally, the job as a teacher _____ be challenging, for I sometimes _____ deal with some smarter but less diligent students.
—I'm sorry I didn't make it to your party last night. — __________. I know you're busy these days.
__________ to the sun for a long time will do harm to your skin.
His __________ description of his adventure in the forest made us want to have a try ourselves.
I don't want any reward for my help; I gave it __________ out of friendship.
Nowadays,there is a __________ increase in children's creativity, for they are greatly encouraged to develop their talents.