什么是宾语补足语？
宾语补足语是为了补充宾语意义，使句子更完整的一种语法成分。宾语补足语的构成有五种形式，分别是：名词、形容词、动名词、不定式和从句。
第一种形式：名词补足语
名词补足语通常出现在及物动词（如make，find，consider等）后面。例如：“I find the idea interesting.” 中，“interesting”就是名词补足语。同样地，以下句子中都有名词补足语：
They made her captain of the team.
She called him a liar.
The judge declared the man guilty.
第二种形式：形容词补足语
形容词补足语通常出现在某些及物动词的后面或是连系动词后面。例如：“I feel tired today.” 中，“tired”就是形容词补足语。同理，以下句子中都有形容词补足语：
I find the movie boring.
She seems happy about the news.
He made his parents proud with his achievements.
第三种形式：动名词补足语
动名词补足语通常出现在及物动词（如keep，leave，catch等）后面。例如：“She keeps everything clean.” 中，“clean”就是动名词补足语。同样地，以下句子中都有动名词补足语：
I left the party feeling relieved.
The teacher caught the student cheating on the exam.
She entered the room singing a beautiful song.
第四种形式：不定式补足语
不定式补足语通常出现在及物动词的后面。例如：“He wants to go to the store.” 中，“to go to the store”就是不定式补足语。同样地，以下句子中都有不定式补足语：
She needs to finish her homework first.
I asked him to come to the party with me.
The teacher told the students to stay quiet during the test.
第五种形式：从句补足语
从句补足语通常出现在及物动词后面，用来解释或说明宾语。例如：“I believe that he is innocent.” 中，“that he is innocent”就是从句补足语。同样地，以下句子中都有从句补足语：
The boss thinks that the employee did a good job on the project.
She hopes that she will pass the driving test.
He fears that he will be late for the meeting.
宾补和双宾语的区别
宾补和双宾语都是由及物动词引起的对句子补充的成分，但它们也有一些区别。
宾补概括地来说是对动词宾语进行补充，它是一个说明、描写、补充宾语的成分，常有动名词、不定式、形容词、名词和从句等形式。而双宾语则是指一些及物动词后面可以接两个宾语，一个直接宾语和一个间接宾语，间接宾语常表示人，而直接宾语往往是物。常见的双宾语动词有give、show、write等。
例如：
He showed me his new car. (双宾语)
He found the movie boring. (宾补)
I want to learn how to play the guitar. (宾补)
因此，我们可以通过区分动词后是否有两个宾语来判断句子中是宾补还是双宾语。