We can never expect a bluer sky ________ we create a less polluted world．

A．until         B．if            C．unless            D．when

—Would you please keep quiet, Sally? The weather forecast _______．

—Oh, I’m sorry I didn’t realize it．

A．is broadcast                                               B．is being broadcast

C．has been broadcast                                     D．had been broadcast

_________by many different kinds of dancing, Martha Graham developed her own personal dance style．

A．Influencing           B．Influenced            C．To Influence          D．Be influenced

It will be sad not to see you during the Christmas holiday ______families get together

A．before          B．when         C．that         D．since

It cost me a fortune，but I don’t regret ______ a year traveling around the world．

A．to spend         B．to be spending           C．spending           D．spent

Around 15,000 officials gathered in Copenhagen, trying to map out an effective strategy ____ the battle against climate change．

A．to win          B．will win         C．winning        D．won

Liu Xiang’s performance at the Shanghai Golden Grand Prix has told his fans a fact _____ he has been back on winning track．

A．when        B．that          C．whether        D．which

— How was the televised concert last night?

—Terrific! Rarely _______ such a large audience．

A．a(chǎn) concert attracted                               B．did a concert attract 

C．a(chǎn) concert did attract                            D．a(chǎn)ttracted a concert

The local government plans to bring in new laws ______ parents to take more responsibility for their children’s education．

A．forced           B．forcing          C．force          D．having forced

Many people in the city wonder _____the city officials have the information they need to solve the problem．

A．that          B．which            C．what              D．whether