In this particular sentence, the 'and' emphasises the lower cost.

Interested in Language
A newly developed jumbo rocket, which is expected to
carry the United States into its next phase of space exploration,
will be able to deliver a heavier load of instruments into orbit than the space shuttle can, and at a lower cost.![]()
Question: In my opinion, the sentence may be not wrong , but at the same time 【, and】 is unnecessary,
even the sentence is better and more concise if 【, and】 is cut.
Is my opinion right?
Sincere thanks to dear teachers!
In this particular sentence, the 'and' emphasises the lower cost.
The original is fine IMO, and the way it is written turns it into two clear points. You can remove , and if you like.
No, but they appear in the same sentence as 'the space shuttle can'. Unless there is clear evidence to the contrary, I think we have to assume that the writer knew his/her times, tenses, and the state of the space shuttle program.
ps (a little later): The sentence appears here, in a post written in 2009. It probably appears elesewhere, but that' good enough.
Whenever the words were said or written, 'can' is correct grammatically unless the speaker knew that the space shuttle program had ended and mistakenly thought that 'can' can be used for past time. I really don't think our members benefit very much from this sort of conjecture.
Bookmarks