文法 - 英檢

這是寫作真經的參考範例，我對裡面的一些文法有疑問

This is beause even being programmed to copy human creations,(要加that嗎)
computers never produce their own unique msterpieces.

因為有開頭的this is，逗號後面不用加that來代表先行詞this is嗎?


She points out that small businesses have a higher closure rate in their first
five years, and thus in terms of job security,(沒有連接詞) working in large companies
certainly overweioghs setting up a new business.

第二句有and ,而且又不是完整句子，所以第三句才不用連接詞嗎?

Nevertheless, the professor clearly indicates that even though large companies
may be reducing welfare offered to their employees, self-emplyers have to
realize that as soon as they start their own businesses,(為什麼沒有連接詞) all
benefits are dug out of their own profits.


另外，整合寫作的最後一段不用加conclusion嗎?
請各位高手解答，謝謝



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