This research aims to describe the seller illocutionary speech act's form, type, and function in offering merchandise at the Bukittinggi City Market. This study is descriptive research that takes a qualitative approach. This research's data is in the form of the seller's speech when offering merchandise at the Bukittinggi City Market, specifically Lereng Market, Ateh Market, Bawah Market, Los Lambuang, and Ramayana. In the data provision stage, the matching method is used, tapping is the basic approach, and the listening-engagement technique (SLC) and free-engaged involved listening (SBLC) techniques are the follow-up techniques. In addition, recording and note-taking methods are utilized. In the data analysis stage, the matching approach is utilized, with the initial technique consisting of sorting the determining elements (PUP) and the subsequent technique consisting of differentiating comparisons (HBB). The results of the data analysis are provided informally. The result of this research, the types of speech acts employed by sellers to advertise their products include speech actions with a mode (1) declarative, (2) imperative, (3) interrogative, (4) imperative-interrogative, (5) interrogative-imperative, (6) imperative-declarative, and (7) imperative-declarative. The speech acts that are performed are direct and indirect. The role of illocutionary speech acts utilized by sellers to offer goods is in the form of illocutionary speech acts: (1) Forceful with the intent of implying and asserting; (2) Directive having the intent to command and coerce; (3) Commission intended for offering; and (4) Expressed to praise and appreciate

This study describes the types of phonological changes that occur from the Minangkabau protolanguage in an isolect of Koto Tinggi. The research is conducted by applying listening and speaking methods, as well as recording and note-taking techniques in the process of providing data. Triangulation techniques are used to test the validity of the data. Furthermore, the data are analyzed by using a top-down reconstruction approach and an articulatory phonetic method. After being compared, the data are grouped based on the types of sound changes. The data analysis results are presented descriptively using formal and informal methods. The result shows that Minangkabau protolanguage undergoes phonological changes in the isolect of Koto Tinggi in the form of (1) lenition; (2) fortition; (3) dissimilation; (4) sound loss, which includes apheresis, syncope, apocope, and haplology; (5) sound addition, namely prothesis and paragoge; and (6) diphthongization process. Phonological changes do not occur in all sounds and are incomplete in all positions.