1.
Online group buying is now extremely popular, with one well-known group buying Web site's revenue jumping from NT$13 million last August to NT$27 million at the end of last year, and an average of more than 700 new groups being established each day.
請問句末的each day為何不加in，變in each day呢？兩者有通用嗎？
2.
She suggests doing someresearchbefore taking part in a group buy and that the only way to save money smartly is by staying aware of the price of the goods you want to buy.
請問before是因為它是介系詞，所有後接動名詞taking嗎？名詞是否也可接於before後方呢？
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