(2013·江西南昌一模)It hasn't been made clear ________ the new underground line is to be open to traffic.
A．when B．that
C．what D．where
(2013·辽宁五校联合体第一次考试)What impresses me most is ________ he appears in front of others, he wears a sincere and charming smile.
A．what B．which
C．that where D．that whenever
(2013·河南开封一模)It is announced that big prizes will go to ________ finishes the assignment on time.
A．whom B．who
C．whomever D．whoever
(2013·四川省乐山一模)The pupils were playing games in the classroom ________ a gunman entered and began shooting wildly at them.
A．while B．when
C．as D．before
(2013·成都第一次诊断)Actually, the London Olympic Park is built ________ there used to be a poor area called East London.
A．what B．when
C．where D．why
(2013·厦门第一次质量检查)You had better book rooms at the hotel in advance ________ you should find no room on your arrival.
A．so that B．even if
C．in case D．now that
