The first sentence starts with infinitive phrase and thus should have a subject. Since it doesnt have a subject its incorrect.

second subject again is an adverbial clause and has a same problem. besides the use of "due to" in the second sentence is incorrect. should be replaced by "because of"

"Due to" should be used in a sentence when it can be replaced by "caused by" and after replacing the sentence still remains logical............

another mistake i see in second sentence is the use comparative form- higher costs. i feel that a simpler adverb should have been used instead of comparative. high cost...

To increase efficiency, more cars were produced.

The first sentence starts with infinitive phrase and thus should have a subject. Since it doesnt have a subject its incorrect.

@ force,

can u please justify your point in red i didn't get this rule?? second, if u are suggesting that a noun is missing in the infinitive phrase, then the word "efficiency" is a noun there...please elaborate your point.

yes my point is that the sentence doesnt have a subject. Who is the doer of the sentence. The sentence has a noun.. thats fine. but it still doesnt have a subject. who is doing this entire act???? besides it doesnt have a verb hence its still a phrase.

i was answering to the question- why this form is incorrect or not preferred. since the sentence starts with a phrase it lacks the clarity of thought. the better way would have been

the company produced more cars to increase .... or
more cars were produced to increase ....

in this construct the dilemma is that "to increase efficiency" is being modified by "more cars"....
the problem is are we modifying "to increase" or "efficiency" in both ways... the context is not very clear.
alternatively, i can also explain this using- cause and effect

example----
to increase score, more study is needed.

the reason why this sentence is awkward is because we have written the effect first instead of the cause. this could have been corrected by saying...

study more to increase your score.
or
you should study more to increase ...

Thanks force5. Your explanation is very good. But I have some other questions about infinitive and passive voice.

In your example, you used "More cars were produced to increase efficiency" and you said this is ok. My question is, in this case, is there a clear actor or subject for the infinitive or is the doer of the action not needed? I thought the placement of the infinitive doesn't make or break the grammatical acceptance:

1. The company produced more cars to increase efficiency.
2. To increase efficiency, the company produced more cars.
3. More cars were produced to increase efficiency.
4. To increase efficiency, more cars were produced.

The first 2 are of course ok. If the 4th is wrong because there is no doer, why the 3rd is ok?

Thanks

capnx wrote:Thanks force5. Your explanation is very good. But I have some other questions about infinitive and passive voice.

In your example, you used "More cars were produced to increase efficiency" and you said this is ok. My question is, in this case, is there a clear actor or subject for the infinitive or is the doer of the action not needed? I thought the placement of the infinitive doesn't make or break the grammatical acceptance:

1. The company produced more cars to increase efficiency.
2. To increase efficiency, the company produced more cars.
3. More cars were produced to increase efficiency.
4. To increase efficiency, more cars were produced.

The first 2 are of course ok. If the 4th is wrong because there is no doer, why the 3rd is ok?

Thanks

They're all fine, and I think you are seeing why they are fine grammatically -- the movement of an adverbial modifying phrase to the front of a sentence is acceptable and common. The problem is not with the passive voice; it is absolutely acceptable to have sentences in the passive voice without a prepositional phrase indicating the agent (as Mistakes were made or The crime was solved is fine without by my mother or by the detective).

So why would your tutor tell you not to do that? Ultimately, adverbial modifiers are most at home close to the verb, and they are most clear there. That said, there are many contexts where greater clarity is achieved by movement of the phrases away from the verb:

In theory, theory and practice are the same; in practice, they aren't. (the context for the comparison moved to the front of the clauses)
vs
Theory and practice are the same in theory; they aren't, in practice.