should

      （尤用于纠正别人）应该，应当used to show what is right, appropriate, etc., especially when criticizing sb's actions

      （提出或征询建议）该，可以used for giving or asking for advice

      （表示预期）应该会，可能used to say that you expect sth is true or will happen

      （表示与预期相反）本应，本当used to say that sth that was expected has not happened

      （与 I 或 we 连用代替 would，表示虚拟结果）就将used after or instead ofwould for describing what you would do if sth else happened first

      （表示可能）假如，万一used to refer to a possible event or situation

      （在间接引语中用作 shall 的过去时）used as the past form ofshall when reporting what sb has said

      （用于 that 引导的、表示建议或安排的从句中）used afterthat when sth is suggested or arranged

      （用于许多表示感情的形容词后的 that 从句中）used afterthat after many adjectives that describe feelings

      （与 I 和 we 连用，表示客气地请求）used with and in polite requests

      （与 I 和 we 连用，表示没有把握）used with and to give opinions that you are not certain about

      （表示十分赞同）used for expressing strong agreement

      why, how, who, what ~ sb/sth do

      （表示拒绝、恼怒或惊奇）used to refuse sth or to show that you are annoyed at a request; used to express surprise about an event or a situation

      （表示假如对方看见或经历某事物，一定会感兴趣或吃惊）真该，真应当used to tell sb that sth would amuse or surprise them if they saw or experienced it