【C9】A．tillB．whenC．whereD．although

【C16】A．whetherB．whenC．whereD．why

【C9】A．soB．whenC．asD．whereas

【C15】A．tillB．whenC．whereD．although

A．WhetherB．WhenC．IfD．Although

【C16】A．BecauseB．WhenC．BeforeD．Although

【C3】A．whatB．whenC．thatD．where