A                             is a tube through which a person swimming just under the surface of the sea can breathe.

Scientists warn that many of the world’s great cities are                                                                                           flooding.

Silence                                        the theatre as the audience awaited the opening curtain with expectation and excitement.

The government is aiming                                              50% reduction                                                                      

unemployment

When the kids asked him about his girlfriend, he’d go as red as a                  .

Many young people in rural areas don`t want to spend their lives on the farm like           parents.

The trouble with James is that he never                                                                                      on time for a meeting.

The world’s biodiversity is declining at an unprecedented rate, which makes wildlife              .