【B13】A．whileB．whichC．wheneverD．when

【C11】A．thatB．whichC．ifD．when

The only candidate______ can hope to defeat him finally quits.A．whoB．whichC．thatD．when

【C19】A．asB．whichC．thatD．when

The street garden is located in______used to be a market place.A．whereB．whichC．whatD．when

Do what you think is right,______they say.A．whateverB．whicheverC．wheneverD．however

It was not until 1920 ______ regular broadcast began.A、whileB、whichC、thatD、since