is there a way to know which words are grouped?
在这个项目的研究上


If you treat 目的 as a noun, then 项 has to be a classifier. But there's already a classifier 个 before it, (项 is not the right classifier for 目的 anyway), therefore, we can eliminate the possibility of "目的" in this sentence being a noun. Which mean 项 is not a classifier but a part of the compound word 项目 (item)

It  all make sense, because we know "个" is a classifier for "项目" (item)

"项" itself is a classifier, but it doesn't work with "目的"(goal) (the classifier of 目的 is 个) 


  在这个项目(的)研究上 = about the study on this item


的 is an adjective marker that turn 这个项目 into an adjective phrase "这个项目的" for the noun 研究 (study) - what study? this item's study

Lenny wrote:


  is there a more ambiguous kind of sentence? surely there must be, that's more of what I'm trying to get at 


Yes, for example, the following sentence can be interpreted differently depend on where you slight pause between words

"是個 人用的 工具" = "是個 (is a)  人用的 (for human use) 工具 (tool)" = "is a tool for human use"

"是 個人用的 工具" = "是" (is) 個人用的 (for personal use) 工具 (tool)" = "is a personal used tool"

Both examples are grammatically correct,  you have to listen to how it is read to determine it is "是個 . 人用的" or "是 . 個人用的"

Or you can look for hints in the context to determine the correct interpretation

One fun one, but it has to do with punctuation marks:


  下雨天留客天留人不留


1. 下雨天留客, 天留人不留 (It is raining as if the heaven wanted to keep the guest here, but the host doesn't keep the guest even the heaven does)

2. 下雨天, 留客天, 留人不? 留! ("It is a rainy day, it is a day to keep the guest, do you keep the guest?" "Yes I do!"