Rewrite the sentence in the passive ​

I have been examined by a doctor and I was told to rest at home.

It was in the 19th century that anaesthetics was invented by them.

More advances in medicine are being made by scientists every year.

The wound will be stitched by them now and the stitches are removed next week.

The fact that vitamins could cure many diseases was discovered by Kazimierz Frank, a Polish scientist.