The group’s research has done much to our knowledge of the HIV virus.
He seemed to be looking for the words ____ he could express his idea.
--- Jim, do you have the time? --- _______. --- Never mind. Thanks anyway.
. She thinks no one knows how much she likes him, but her face when I said he’d be there really ______!
It _________ there is a disaster _________ people will think much of the safety.
-----Why are you so frustrated? -----I’d like to make a call, but my cellphone is out of __________ again.