This study explores interactions among language learners with the support of online resources in a collaborative writing task and how online resources assisted collaborating learners in the meaning-making process. The study was conducted in the freshman English course at a national university in Taiwan. Fifty-six students constructed an essay in pairs firstly "without" the support of online resources, and subsequently constructed another essay "with" the support of online resources. Each pair's interactional patterns and dynamics of peer scaffolding across the two settings were examined. The findings show that the availability of online resources fosters a variety of interaction characteristics among learners with varied collaboration orientation. Results also suggest that learners' collaboration predisposition at the onset plays a critical role in influencing the way they used online resources to support their interaction. This study thus suggests that learners' collaborative patterns and their use of online resources have mutual impact, which may inform teachers seeking to integrate online resources to enhance their students' collaborative learning.