Are these sentences grammatically correct?

[dilodi83]

Could you tell me if these 3 sentences are grammatically correct, please?

- They have tried to throw light on and to understand, through a careful study and analysis of the text, who might be the author and what time the translation goes back to.

- They think Alfred could not have been the author of the translation at all, but he surelly could have been the person who had paid /would have paid for it.

- For example, if the author is speaking about someone who was still alive during his time and he was not during the translator's time, he adds that, in the meantime, those people had died. In another case, for example, if the author is writing of a particular political situation of his time or of a monastery, the translator, if the situation has changed, modifies and modernizes the story according to his time.

Thanks very much in advance.

[mykwyner]

Could you tell me if these 3 sentences are grammatically correct, please?

- They have tried to throw light on and to understand, through a careful study and analysis of the text, who might be the author and what time the translation goes back to. This sentence ends with an awkward preposition.

- They think Alfred could not have been the author of the translation at all, but he surelly [surely] could have been the person who had paid / Use a coordinating conjunction "or" here instead of the virgule would have paid for it.

- For example, if the author is speaking about someone who was still alive during his time and he was not during the translator's time, he adds that, in the meantime, those people had died. In another case, for example, if the author is writing of a particular political situation of his time or of a monastery, the translator, if the situation has changed, modifies and modernizes the story according to his time. This is probably grammatical, but very difficult to read. Rewrite it with fewer interrupting phrases.

Thanks very much in advance.

Try these corrections.