2012年10月28日 · 1. PCBs have been shown to cause cancer in animals. 2. PCBs have shown to cause cancer in animals. 1. is a passive: it means that someone has demonstrated or …
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2013年10月6日 · Thank you! 1. Tom challenges his counterpart's view with several reasons below. 2. Tom challenges his counterpart's view with several reasons as shown below. 3. Tom …
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2012年7月5日 · You have two questions here. 1. Both "as shown" and "as seen" are correct. There is a difference in emphasis. "As shown" focuses on what the graph or chart does. "As seen" …
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