In organic farming, natural waste from animals are made use of ________ the fields.
It is generally believed that _____ study, we can gain both knowledge and skills.
At the foot of Yuelu Mountain ____, which is one of the most famous middle schools in China.
A Hope School will be built in_____ used to be a temple.
There is clear evidence _____ smoking does harm to our health.
I was lying in bed last night when I felt the house______. Then everything became silent.