名词性从句问题.Do you think my clothes fit well 这个句子的主句是Do you thin

my clothes fit well 是个从句,整体做think的宾语.所以是动宾

you've是you have 的缩写.what you've done 是从句做be sure for 的宾语,for是个介词.所以是介宾.
从句是个句子.也有主语,谓语,宾语.
再问： do you是什么成分？
再答： do you like it ? Do you think my clothes fit well ? 对比一下，疑问句一般形式;助动词+主语