1. interior=inner=inside 内部的 adj.
2. change=shift=alter=transfer 改变v.
3. establish=build=found=set up=start 建立 v.
4. official=authority=leader=supervisor 官员 n.
5. isolated=inaccessible=distant=remote=faraway 隔离的`, 边远的 adj.
6. collapse=fall=fall over=fall down 倒塌 v.
7. destroy=devastate=wreck=obliterate 毁灭 v.
8. absorb=digest=take in=assimilate 吸收 v.
9. severe=serious=stiff=heavy 严重的 adj.
10. purify=refine=distill 净化 v.
11. hidden=disguised=concealed=veiled 隐藏的 adj.
12. decline=decrease=reduce=fall=drop 下降 v.
13. deteriorate=get worse=go down=decline 变坏 v.
14. recognize=know=identify=pick out 认出 v.
15. conclude=summarize=come to/reach the conclusion 得出结论 v.
16. adapt to=get used to=become accustomed to=adjust to 适应 v.
17. initiate=start=launch=open=set in motion 开始，发起 v.
18. refer to=mention=allude to=touch on 提到 v.
19. identify=name=recognize=diagnose 确定，认同 v.
20. request=demand=claim=petition=appeal 要求 n.