1. whilst
We were able to visit the Museum of Obsolete Computers whilst we were in Munich.
I was working hard whilst you were on holiday! My daughter is very calm, whilst my son is always full of energy.
"Tall" and "short" we use for people, whilst "high" and "low" we use for things.
They did it whilst she was asleep in the house.
If you are going to the library this afternoon, would you please return two books for me whilst you are there?
Whilst at university, Xiaowang held the post of class monitor.
However, what's interesting is that whilst there are people whose computer use has become a problem, there are also people who have recovered from illness because of using computers.
Juan was Costa Rican, whilst Pierre and Jack came from Réunion and South Africa respectively.
When answering this question, some people might put forward this kind of example: "Chinese people are very hospitable, whilst English people are more reserved."