I shall go to see the doctor tomorrow.
I am ill.
I have fallen ill.
Tom did not come to school yesterday.
You may catch a cold.
I have caught a cold.
While crossing the English Channel, we stayed on deck all the time.
I felt sick while crossing the Channel.
I am feeling bad today.
I have pain in my right side.
I have just been examined by a good doctor.
I shall not come to school until Monday.
I spent a month at a seaside resort.
My health has greatly improved since then.