關系詞，即體現句子之間關系的詞或詞組。也有不少人稱之為信號詞，或者是連接詞。不管在雅思聽說讀寫四門中的任何一門都需要用到這類詞，以使得句子更加流暢，句意更加明晰。分析認為，關系詞可分為兩大類：
1. 同向關系詞
同向關系詞，即用上此類詞或詞組，句子內部或句子間的方向沒有發生改變，只是根據前面的句意進一步延伸和細化。將其歸納為：
舉例關系詞：for example, for instance,e.g., such as, like, take sth for example.
類比關系詞：like,alike, similar, same,as
選擇，并列和遞進關系詞：or,either…or, and, as well,also, besides, apart from, in addition, what’s more,furthermore, moreover
因果關系詞：表示由引起的，后接原因的詞或詞組：because，be cause of，as a result of, as a consequence of, due to, result from, be attributed to, be contributed to, arise from, owing to, thanks to, in that
表示導致，后接結果的詞或者詞組：so, therefore, thus, as a result, as a consequence, lead to, result in, attribute to, contribute to, give rise to, bring about, generate
總結關系詞：in conclusion, to conclude,to sum up, in sum, all in all, in brief
2. 逆向關系詞
逆向關系詞，即用上此類詞或詞組，句子內部或句子間的方向發生改變，前后句子意思形成相反關系。總結發現，這類詞包含：
否定關系詞：not,none, no, never, non-,dis-, un-, in-, im-, -less, few, little, hardly, barely,seldom, neither…nor
轉折和讓步關系詞：but,however, yet, nevertheless,nonetheless, in fact, actually, despite, in spite of, although, even though,though
對比關系詞：unlike,by contrast, in contrast, on the contrary, conversely
(注：以上各類關系詞中所舉的例子僅僅只是常見的一部分)