Provided / What if you do exercises regularly, you will lose weight.
In case of / As long as a mistake in this chemical formula, a disaster could happen.
You had better not / must not drink water in foreign countries. I am often suspicious of it.
I wouldn’t go to see the dermatologist even if / what if I had a severe rash.
II. Underline the correct form of the verb.
My brother Kevin has always been a fitness fanatic. He believes that if you look after / looked afteryour body, it will look after you. Whenever anyone is ill, he says / will say “If they had taken care of themselves, they wouldn’t get / wouldn’t have got ill. And the same thing happens / will happen to me if I didn’t keep fit / don’t keep fit”. I would often say to him, “If I were you, Kevin, I would try / would have tried to slow down a little bit. You will wear yourself out”. Last month, however, I went to the doctor’s and he told me that I was unfit. He said that if I don’t start / didn’t start taking regular exercise, I would be / would have been in danger of becoming ill. I started going to the gym with Kevin and, after a week, I said to him “I feel better already. If I know / had known how good it feels to exercise, I would start / would have started years ago!”