The concept of teacher enthusiasm was first introduced in 1970s when it was considered as an instructional behavior including non-verbal communication behaviors such as smile, eye contact, gesture, facial expressions, and the like. This led to a uni-dimensional approach to the definition of enthusiasm making it equated with teacher enjoyment (Kunter et al., 2011). This conceptualization regards teacher enthusiasm as quality of effective teaching that affects learners’ academic performance by indicating more energy and interest in the subject, the contents, and their presentation in a dynamic, motivating way. In this perspective, enthusiasm pertains to teachers’ expressiveness and capability to convey the significance and inherent value of the materials to their pupils (Kim and Schallert, 2014; Wang and Guan, 2020).

The other perspective that is bi-dimensional perceives teacher enthusiasm as an emotional-behavioral characteristic involving individual disposition and emotion (Kunter et al., 2011). It is clarified as the affective experiences of enjoyment, excitement, and pleasure together with their expressive behaviors that are actually occurring and manifesting such experiences in the classroom (Kunter et al., 2011). This recurring emotion can be related to the subject matter and the teaching activity. Moreover, the construct of teacher enthusiasm like other positive emotions is claimed to be contagious in that it can be easily transmitted to students whose motivation, vitality, attention, engagement, and interest are correspondingly improved by this factor (Zhang, 2013; Lazarides et al., 2019; Peng, 2021).

Teacher enthusiasm in the class involves various behaviors and practices. Hence, it includes different components as evidenced in the literature. For instance, eight constituents for the construct of teacher enthusiasm include: (1) varying speed and tone of voice, (2) maintaining eye contact, (3) using demonstrative gestures, (4) body movement, (5) showing a lively facial expression, (6) using illustrative words, (7) showing willingness to accept students’ ideas and feelings, and finally (8) maintaining vitality. In a similar vein, the following nine elements shape a teacher’s enthusiasm (Table 1).

Both these studies considering the constituents of teacher enthusiasm have been conducted decades ago meaning that recent studies on the construct have turned a blind eye on the new possible components in EFL contexts and across cultures. This can be a direction for future research aiming to add to or modify the existing components of teacher enthusiasm.

The concept of teacher clarity is a relational behavior belonging to interpersonal communication skills (Comadena et al., 2007; Xie and Derakhshan, 2021). As pinpointed by Bolkan (2017) and Comadena et al. (2007), the construct of teacher clarity pertains to both verbal and non-verbal cues, strategies, and approaches that teachers utilize to ensure that their pupils have mastered the content and processes of the course. Hence, having verbal and non-verbal clarity is essential for EFL teachers to inspire meaning in the minds of the students regarding the course, its content, processes, and purposes (Bolkan, 2016; Zheng, 2021). There is enough research evidence that teacher clarity causes various positive academic outcomes such as students’ increased motivation, classroom engagement, participation, attendance, critical thinking, empowerment, and immediacy (Finn and Schrodt, 2012; Titsworth et al., 2015; Bolkan, 2017; Zheng, 2021). Another probable benefit of teacher clarity in EFL contexts relates to the reduction and removal of negative variables like boredom as clarity generates course comprehension, positive rapport, credibility, and academic interest. As a result, students rarely get entangled in the tedium and tiredness of the class in case they have a clear teacher who strives to engage students in the course process and content (Zheng, 2021).

As one of the instructional communication theories, the Rhetorical/Relational Goal Theory (RRGT) that was introduced by Mottet et al. (2006) aims to reveal the nature and operational process of instructional communication. Moreover, the theory posits that classroom teachers and learners have rhetorical and relational goals to which they wish to reach (Mottet et al., 2006). Consequently, each classroom draws on the needs/goals of both students and their teacher who have relational needs (e.g., to be admitted) and rhetorical needs (e.g., to complete a task and to get a high grade). This is the duty of teachers to simultaneously manage these needs via their behavioral choices in the classroom (Frymier, 2007). It is believed that teachers’ rhetorical and relational behaviors serve diverse purposes. For example, they may use “clarity” as a rhetorical instructional communication behavior to improve the quality of teaching and influence students’ beliefs, behaviors, and practices in the classroom through determining their intended instructional messages (Beebe and Mottet, 2009). Teachers may also use rhetorical and relational behaviors to establish a positive rapport with their students in the classroom (Myers, 2008).

In sum, it can be argued that in any educational setting, teachers need to employ a combination of rhetorical and relational behaviors to produce positive outcomes (Myers et al., 2018). Those behaviors can be influenced by other factors like teaching context, teachers’ personality, credibility, clarity, immediacy, homophily, and learners’ perceptions (Beebe and Mottet, 2009; Zheng, 2021). Yet another teacher-related factor that can affect classroom rhetorical and relational behaviors is teacher enthusiasm and its role in reducing students’ negative emotions (e.g., boredom), which has been limitedly explored in L2 contexts.

The concept of boredom is very complicated and hard to be defined by a single characteristic. It is a combination of feelings such as disengagement, dissatisfaction, lack of attention, amotivation, demotivation, lack of energy, and wrong time perception (Pawlak et al., 2020). Consequently, offering a one-size-fits-all definition for it has long been impossible. This might be due to its unobservable and multi-layered nature and similarity to other terms such as sluggishness, inactivity, tedium, and indifference (Daniels et al., 2015; Weinerman and Kenner, 2016). However, most researchers in this domain certify that boredom is a damaging, negative, silent, fleeting, deactivating, and disappointing emotion affecting learners’ learning process (Li et al., 2021). It ruins the pleasure of teachers’ and learners’ practice and generates disengagement and frustration that finally end in poor academic performance.

With regard to its dimensions, boredom has been claimed to include three dimensions of valence, activation/arousal, and objective focus. Valence refers to the amount of pleasantness/unpleasantness of a feeling, while activation concerns the physical/cognitive activation/deactivation of an emotion. Finally, objective focus concerns if the feeling is activity-oriented or outcome-oriented (Pekrun, 2006).

Boredom emerges and takes root from various factors and sources such as those related to students, teachers, materials, and equipment (Li, 2021). As for student-related factors, low language proficiency, motivation, interest, fatigue, and a negative appraisal are the key sources of boredom. Concerning teacher-related causes, poor teaching abilities, untimed feedback, boring speech/presentation, and poor classroom rapport are the sources of boredom. Furthermore, monotonous and unchallenging classroom tasks and materials are task-related sources of boredom. Finally, inadequate amenities and tools in the class (e.g., digital tools, audio-visual tools, whiteboards, and markers) may generate disengagement and boredom among teachers and students (Daniels et al., 2015; Derakhshan et al., 2021a,b; Li, 2021).

Despite these challenges and causes, students and teachers can employ many strategies such as analyzing issues from a different outlook, utilizing new resources, resorting to activities that require physical activity in the class (e.g., standing up, walking, and using music; Kruk and Zawodniak, 2018). As boredom is new in L2 education, few studies have yet been conducted on this critical emotion being limited to unraveling its causes and solutions. However, more studies are needed in this area to see if teacher-related variables like enthusiasm and clarity can prevent students’ boredom in English classes or not.