Human understanding of the brain has gradually expanded from cell level to macroscopic level such as brain network and connectome, trying to better elucidate its function by observing interconnections between different regions [1]. According to anatomical structures and functional magnetic resonance imaging (fMRI) activation pattern, scientists divide the brain into different regions. Each region has its own function, and some regions are tightly connected to form subnetworks. Subnetworks exchange information and make up large brain networks to perform complex tasks [2–4]. Nowadays different literatures classify the brain from six core brain networks to hundreds of smaller brain units [5]. The language network is mainly located in the left brain, which can be divided into a core language network and several secondary language networks (hereinafter referred to as the core and secondary networks). The core network is responsible for both high-level language processes such as grammar, semantic production, and comprehension, and low-level language processes such as speech signals acceptation and speech musculature coordination [6]. But only the core network is not sufficient for communication in the real world. Language should also express feelings, store thoughts, perform logical deduction, etc. Therefore, secondary networks are needed to carry out these additional functions [7–9]. Damage to any part of the network may lead to language dysfunction. With the application of techniques such as direct electrical stimulation (DES), electrocorticography (ECoG), functional magnetic resonance imaging (fMRI), and diffusion tensor imaging (DTI), it has been possible to roughly map the anatomical structure and corresponding functional of the core and secondary networks [2, 10].