新概念英语第二册课后习题答案详解Lesson 31练习答案 Key to written exercises1关键句型练习答案A What was happening： was telling (1.1)；was still smiling (1.10)What happened： retired(1.2)；saved(1.5)；bought(1.6)；had(1.7)；employed(1.9)；smiled when he remembered (1.9)；openedcame inwanted(11.10-11)What used to happen： used to work(1.3)；used to work(11.4-5)；used to make(1.7)C worked/was workingsat/was sittingwas lookingwere passingstoppedgotwere/had beenused to come/cameused to go/wentwerequarre
