单项选择题
The present difficulties（）from our failure to deal with the problem when it first arose.
A.step B.stem C.steer D.sponsor
单项选择题 The one pleasure that Einstein（）his great fame was the ability it gave him to help others.
单项选择题 She was（）what she had written so as to make the theme stand out more clearly.
单项选择题 No effective（）has been found for this fatal disease which claims thousands of lives each year.
