Once new difficulties __________ in your work, it's always important to use your brains.
.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 .
As she lives quite near our school , she often goes to work on an electric bike ___ in her car .
The board are discussing the possible _____ they can take of the present economic situation.