Once new difficulties _____ in our study, we should learn to use our brains to solve them.
—___does much good to your health—Thank you for your advice,and I must stop smoking as you say
There are laws in some coutries which prohibit advertisements from___at inappropriate time and places
I am going to the bottom of this!I___hanging back(退缩)
I hate___when I hear someone cheat in the exam
We had wanted to finish our task by noon,but it didn’t quite___as planned