He yanked and held on to his friend who was about to leave.
Tips
grammar
扯 (chě, to pull) + 住 (zhù, resultative complement: 'firmly / in place'). The pattern verb+住 means the action achieved a 'holding / fixing' result — see also 抓住 (zhuāzhù, grasp), 记住 (jìzhù, memorize), 站住 (zhànzhù, stand still).