本文以首爾大等5大教材為對象，進行分析比較，結果發現，教材裡對5種推測句型的解釋只以「推測、猜測」一語帶過，但這些句型的文法機能異同之說明卻付之闕如，因此造成學習者的誤用及混淆。本文站在外國學習的立場，提出改進建議，並將5種句型容易混淆的部分釐清整理。 겠為很強的主觀推測，即話者依據本身的判斷來進行推測，通常用在第三人稱。之於겠,ㄹ 것ㅇ다相對客觀，而且沒有人稱的限制，一般是根據客觀情報來推測。這兩種用法除了推測外，尚有意志的語意。 相對於겠和ㄹ것이다的相似性，ㄹ것같다、ㄹ모양이다、는가/나보다這3種用法的屬性也很類似，都是透過某些情況來推測，不同的是，ㄹ것같다判斷的依據須為直接經驗，所以較為主觀，此外，人稱的不限亦是差異之處。

This paper focuses on the top five teaching materials from Seoul University. After comparison and analysis, it is discovered that explanations for five kinds of conjecture sentence pattern are limited, which are only explained as supposition or assumption without any further clarification. Because explanation is deficient, learners are easily confused by these five conjecture sentence patterns. From a standpoint of a foreign language learner, this article attempts to present some suggestions for improvement and clarification on possibly confusion parts of these five sentence patterns. The sentence with 겠 is very strong subjective assumption, which means that the person makes supposition is based on his own judgment, which is always used as the third party. Compare to 겠, ㄹ것이다 is objective, and it doesn’t have the restriction of using first-person, second-person or third-person. Also the assumption is usually made by objective information. Compare with the similarity of겠andㄹ것이다, the usages ofㄹ것같다, ㄹ모양이다, and 는가/나are similar, too. Their assumptions are all based on certain situations, however, refer toㄹ것같다, there are two main different points amongㄹ것같다, ㄹ모앙이다, and 는가/나보라, one is that the assumption which is made byㄹ것같라is based on direct experience, the other one is there is no restriction of usage of first-person, second-person, and third-person.