Past Perfect, Past simple

I ____________________ always been very fit and healthy , and I have ____________________ had a serious illness .
However , a couple of weeks ____________________ , I caught the flu . I must admit that until then , I ____________________ not realised just how unpleasant the flu could be .

I had a high temperature for nearly a week , and my whole body hurt . I don ? t think I have ____________________ felt so miserable . It ? s taking me ages to get my strength back . It really bothers me that I haven ? t had enough energy to ____________________ football when I got ill .

In fact , I have even ____________________ to the doctor to ask if it ? s normal to feel weak for so long . He says I ? ll soon feel better . Apparently I ? m lucky . For some people , especially the old and the weak , the flu can be very serious .

Doctors have tried ____________________ years to find a cure for the flu , but they haven ? t found one ____________________ . Fortunately , researchers have developed a vaccine which gives effective protection against the disease . According to my doctor , most of his elderly patients have ____________________ . received their flu shots .