________ we’ve made the promise, let’s keep to it and not give up easily. A . Whether B . Since C . Though D . Unless
答案: B 【详解】 句意:既然我们已经许下了诺言,就让我们信守诺言,不要轻易放弃。 考连词。 Whether 是否; Since 既然; Though 虽然; Unless 除非;根据 “we’ve made the promise, let’s keep to it and not give up easily.” 可知,此处表达的是因果关系,应用 since 连接,引导原因状语从句,故选 B 。