Language development is subject to its interaction and alignment with environments. However, how it interacts and aligns with environments necessitates further research, given current incompatible views and findings on language–context relations, particularly marker–context relations in multimodal or second language's (L2) sustainable development. Thus, this article proposes from the Ecolinguistic Continuum (Xiao, 2021) perspective a multidimensional alignment sustainability model (MASM) verified via instantiating a semio-semantic and semio-pragmatic marker continuum in the first language (L1, Chinese) and examining L1 (English) and L2 (English) written and spoken corpora-driven data. Results showed (1) a semio-semantic and semio-pragmatic marker continuum in both languages, ranging/evolving from the conceptually rich/explicit/formal to the partly conceptual/neutral, finally to the conceptually empty/implicit/informal, a process of uni-bi-multi-functions or grammaticalization-semio-pragmaticalization, and (2) the dis/similarities between L1 and L2 marker use distributions, pinpointing the multidimensional niches for languages' sustainable alignment evolvement/development. The findings corroborate the Ecolinguistic Continuum Paradigm, particularly the MASM, indicating that ideational/referential, structural, interpersonal, cognitive, and psychological functions/meanings of markers emerge dynamically depending on the extent to which they align with their corresponding environments. This view extends previous one-dimensional linguistic and context-related studies and helps unravel the problems in L1 and L2 sustainability development.