Is it correct?

Peter presently takes advantage of John as Mary previously did of Jane.

This is fine, as are all the other sentences you have posted using the same construction.

Matthew, please note that a better title would have been 'Peter presently takes advantage of John....'

Extract from the Posting Guidelines:

'Thread titles should include all or part of the word/phrase being discussed.'

Barb_D said:

This is fine, as are all the other sentences you have posted using the same construction.

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Not exactly the same, tenses are different this time. A native English teacher told me that tenses must be the same while using elliptical construction, do you agree? May I post a URL going to her answers on another site?

Matthew Wai said:

Not exactly the same, tenses are different this time. A native English teacher told me that tenses must be the same while using elliptical construction, do you agree? May I post a URL going to her answers on another site?

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Yes, please post the URL.

Click here to see what she told me, please go to the line beginning with ---- this one is not correct because of the verb tenses.
Did I misread her meaning?

Matthew Wai said:

Click here to see what she told me, please go to the line beginning with ---- this one is not correct because of the verb tenses.
Did I misread her meaning?

Click to expand...

My first comment is that the response you received about ""Hong Kong has not taken a tough stand on the hostage incident as Taiwan did on the Guang Da Xing incident because it must have regard to Sino-Philippine relations" was not the one I would have given.

An easier fix would have been ""Hong Kong has not taken as tough a stand on the hostage incident as Taiwan did on the Guang Da Xing incident because it would have affected Sino-Philippine relations."

MikeNewYork said:

An easier fix would have been ""Hong Kong has not taken as tough a stand on the hostage incident as Taiwan did on the Guang Da Xing incident because it would have affected Sino-Philippine relations."

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Given your above sentence, verb tenses can be different while using elliptical constructions, correct?

Matthew Wai said:

Given your above sentence, verb tenses can be different while using elliptical constructions, correct?

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Yes, depending on what one is trying to say.

There is no reason you cannot use different tenses if you are referring to things that happened at different times.
Adult children often take of their parents as their parents once did of them.

These are all fine. I don't know why the "Ask an Expert" teacher has said it's not okay. I don't know why she said that other thing "made no sense." (It was not grammatical, but it was understandable.) I can't begin to guess what is in her mind. But I wish you would not accept what she said as 100% accurate and question and question that other guidance you have been getting. Reasonable people can disagree on things. She is no more right than the seven or so people who have provided other opinions on these sentences you keep posting.