Reproduction is another cohesive device of words in cloze, that is, words expressing the same meaning appear in different places in the article. Reproduction can be the repetition of the same word or the expression of the same meaning with different words. There is no rule to follow. Every school is different.

Actually, don't just read an article. When you start a direction, you will choose to read a lot of related papers instead of a simple article as a reference. Sometimes. This depends on your own ability. If you have strong engineering ability, minutes. If it is weak, it will take half a year. It may or may not be. It was difficult at first, but only later. It will only get better and better.