, the left square bracket appears without its counterpart. This is useful for creating reverse brackets or for constructing intervals. Note that only non-scalable brackets can be used individually. To change the size, use the
时，则只会出现左方括号，而与其对应的右方括号则不出现。这在创建反括号或构建间隔时很有用。请注意，只有不可缩放的括号才可以单独使用。要修改大小，请使用