【C7】A．howeverB．thoughC．asD．when

【C7】A．BecauseB．ForC．WhileD．When

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【C7】A．althoughB．becauseC．only ifD．when

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【C7】A．ButB．ThoughC．MoreoverD．Nevertheless

答案解析

Hard______they tried, they failed to climb to the mountain topA．ifB．when.C．asD．since

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【C7】A．SinceB．BeforeC．AsD．If

答案解析

【C7】A．howeverB．meanwhileC．thereforeD．moreover

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【C7】A．meanwhileB．butC．asD．while

答案解析