That’s the new machine ______ parts are too small to be seen.
| A．that | B．which | C．whose | D．what |
He was breathing ______ after the relay race.
| A．heavily | B．slowly | C．carefully | D．weakly |
People are concerned about the quality of the air they ______.
| A．hear | B．eat | C．drink | D．breathe |
She walked home by herself, ______ she knew that it was dangerous.
| A．if | B．so that | C．although | D．because |
—Let's go Dutch for this supper, OK?
—No，________this time, as a reward for all your help.
| A．it's up to you | B．it's my treat |
| C．let's talk about it | D．it doesn't matter |
At the United Nations Climate Change Conference, the UN Secretary General points out that，________， the climate situation will get worse and worse.
| A．if not dealing with properly |
| B．unless dealing with properly |
| C．if properly dealt with |
| D．unless properly dealt with |