—Where did you find our chemistry teacher? —It was in the lab ______ he was doing his experiment.
On hearing the news, the girl rushed out without hesitation, the luggage_______on the floor and _________in the dark.
The old men can hardly imagine that they can live in an age _______ most of the daily things are done on the computers.
The guests are looking forward every moment to _______ to China again.
Many students don't want themselves to _______ doing _______ homework.
—English has a large vocabulary, _______?—Yes. Know more words and expressions and you will find _______ easier to read and communicate.