1.Dr. Wang has made much contribution to the theories of modern physics at the ____ of his health.

A.cost

B.disposal

C.mercy

D.expenditure

2.Crisis would be the right term to describe the ___ in many animal species.

A.abolition

B.restriction

C.descent

D.decline

3.Up until that time, his interest has focused almost ___ on fully mastering the skills and techniques of his craft.

A.restrictively

B.radically

C.inclusively

D.exclusively

4.In the ___ of human life the honors and rewards fall to those who show their good qualitiesin action.

A.ring

B.terrace

C.arena

D.ground

來源:可可英語 http://www.ccdyzl.cn/tem4/201503/362783.shtml