We visited Beijing University _______ the first day of our trip.

Our English teacher is ill, and we are all ______ her health.

Robots in the future will be ______ in people’s homes.

What is the most popular way to communicate in China now–WeChat. One of its ____ is that it can send words, pictures as well as voices.

So you are back; are all the students present at the meeting? —Not really, nobody but Lucy and John ___________ in the meeting room.