Read the following passage and circle the letter A, B, C, or D to indicate the correct word or phrase that best fits each of the numbered blanks. Headache is a very common disease. The symptoms (25) _______ a headache are various. People may (26) _______ pains only one side of the head. Sometimes when the pain goes away, the head is sore. People have a headache (27) _______ they work too hard or they are too nervous about something. (28) _______ can help cure the disease but people usually have to do more than taking tablets. They can prevent headaches by changing their diets or their lifestyles or simply by going to bed. 25. A. on B. in C. of D. at 26. A. be B. have C. happen D. take 27. A. when B. but C. so D. and 28. A. Medicine B. Doctor C. Sport D. Fruit