Print first 2 pp. on, e.g., blue paper and the second 2 on, e.g., red. Cut cards on lines, give each student one card. They mix and talk to find matching cards, add appropriate relative pronoun, change third-person "s" if necessary, then write or go to a teacher and say the sentence, then take new cards and do again. Made for Japanese students but appropriate for any ESL/EFL. Feel free to change/adapt for your use.