In English class, our teacher often creates an environment __________ we are given the opportunity to solve problems ourselves.
Being popular with customers , the products _____ well and ____ in two months .
Hill often attends lectures at Nanjing University , chiefly ____ his knowledge about hobbies .
.Saving resources is a basic policy of our country . And it proves _____ to its sustainable development .
._______ after a long walk , Mr Yang called and said he couldn’t come .
.It is ______ to spend money on preventing illnesses by promoting healthy living rather than spending it trying to make people ______ after they are ill .