Nowadays, sending e-mails to each other has become a way ______________ what they think to others.
Shall we go ____ downtown to buy some clothes of high quality?
____ we are alone, we can speak freely.
The chairman thought ____ necessary to invite Professor Smith to speak at the meeting.
It is not expected ____ he said caused so much discussion at the meeting.
He is always ready to help others. That’s one of his _____.