to-verb vs. so that. "there is" a verb?

[YaoguiH232]

Hi all, thanks for your time at the beginning!!
I have two questions,
1): on 2019 OG verbal #687, the answer choice recommend to use "to-verb"(i.e. to drink, to make, etc) over "so that", saying that though they both convey the purpose of the subject, but "to-verb" is better for that question. Can you explain what's the difference between these two on conveying purpose?

2): 2019 OG verbal #691, the correct answer choice writes "estimating the expansion rate of the universe is a notoriously difficult problem because there is no single yardstick by which all distances can be measure." initially i did not choose this answer was because i thought it was a run-on sentence without a working verb, does "there is no single yardstick..." consider as a work verb?

thanks!

[StaceyKoprince]

Hi! Unfortunately, we don't post / discuss OG problems on the forums. There's a copyright ban against posting OG problems publicly (I know lots of forums don't follow that law, but we do). And it's really difficult to discuss OG problems without being able to quote the problems.

I'll give you a little bit of an answer, but if you are taking a class or tutoring, ask your instructor about these problems.

For the first one, this issue is really just an idiom—one of the most annoying things about studying any language. There's no logical rule to follow; it's just "In this circumstance, this is the structure you use" and you have to memorize it.

So when I say "I need to find ways..." that has to be followed by "to (do something)." I need to find ways to study more efficiently. I need to find ways to cook greater quantities of food. It's the same if you say "a way": I need to find a way to study more efficiently. If you say "find a way" or "find ways," it's just followed by an infinitive verb (to X) because...that's the way the language works.

For the second one: This is a weird sentence structure, called an inverted sentence. Here are some simpler examples:

There is a fly on the wall. The verb: is. The subject: a fly. The "regular" sentence would be: A fly is on the wall. But you can turn it around (or invert it) to say There is...(whatever you want to say).

There was an old man at the park.
Verb: was
Subject: man
Regular order: An old man was at the park.

The sentence that you quote is even weirder because there isn't an easy way to write it in the "regular" way. The closest would be something like this: No single yardstick is able to measure all distances.