The policy of the mainland is very clear and straightforward,and the key problem is_____the leaders of Taiwan will accept it.
In front of the classroom___
___sign the contract unless you are sure you understand it.
Eyewitness provides an evidence that he was ___ of the crime.
Wash your hands with soap and water ___ after each contact with the sick person.
After the fun he has had during the holidays, the boy can’t ___ on his schoolwork.