Although the terms cohesion and coherence are often used together, they do not refer to the same properties of text and discourse. Cohesion usually refers to connections between sentences and paragraphs, and coherence can also refer to the organization of discourse with all elements present and fitting together logically. For example, the presence of an introduction, a thesis statement, rhetorical support, and a conclusion can create a coherent essay that is not necessarily cohesive (Carrell, 1982; Chafe, 1994; Scollon & Scollon, 2001).
Cohesion is a surface phenomenon: it concerns the grammatical and lexical features that create ties between sentences, most importantly lexical repetition, use of substituting pronouns (it / these) and linking words (transitions, complex prepositions). A lack of cohesion results in a choppy, unconnected style.
In the excerpt below, the cohesive chain is relatively easy to identify, and several cohesive chains are developed simultaneously without interfering with one another. Chain [1] moves from coastal erosion to it and then to east coast and west coast, coastal erosion, coastal area, and coastal areas, as well as related (and repeated) nouns shoreline and shorelines. Environment and society [2] is connected to cities and villages and then to local people. Cohesive line [3] begins with changes and moves to changed, different, and adjust, and line [4] connects fishing to make their living, fishing, and their jobs (also connected to local people by means of the pronoun their in their living, their traditional ways, and their jobs).
Coastal erosion[1] is a problem throughout the United States, and it[1] occurs on the east coast and the west coast[1]. The coastal erosion[1] will directly influence the environment and society[2] in the coastal area[1]. Cities and villages[2] that are located in coastal areas[1] will experience changes[3] in the shape of the shoreline[1]. When shorelines[1] have changed[1] shapes. fishing[4] in tide pooh and from boats will also need to become different[3]. So, the local people[2] who make their living[4] by fishing[4] will also have to adjust[3] their traditional ways of doing their jobs[4] every day.
Although the text is slightly repetitive, it is highly cohesive and unified. The technique of repeating a word from the immediately preceding sentence is easy to use for L2 writers at most levels of language proficiency. On Improve cohesion & coherence: common techniques there are a number of strategies to enhance both coherence and cohesion of your text.