词汇练习1：
1-10 CACDC; CBAAA 11-20 BDCBA; ABCCA 21-30 DDBBD; CAACB 31-40 CABBA; AACDD 41-50 BABCC; BCACB 词汇练习2：
1-10 BCCCD；DABDC 11-20 DBCDB；CDDDA 21-30 DCABB；DDAAA 31-40 BADDB；BCBCA 41-50 DCCAB；CADBD 51-60 DBCCC；ADCDB 词汇练习3：
1-10 BDDBA; CBADA 11-20 DBDCC; DADBC
21-30AABAA; ADCBB 31< xmlnamespace prefix =\=\ 41-50 BADCD; DDDDC 词汇练习4：
1-10 CDAAD; BAABD 11-20 DBCBA; BBACB 21-30 CDBCC; DABDB 31-40 ABCDD; ABABC 41-50 DCCAC; ADDDC
二． 时态和语态练习答案
1-10 CCDAD; BA ACD 11-20 CDDCA; ABBBC 21-30 AAACD; CBCBD
三．从句练习答案
定语从句：
1-10 BABCB; CDDBD 11-20 DBDAD; CADAB 21-30 DABBC; DBACD 31-40DCDCC; CBCDB 41-50 BCDDD; DDBAD 51-60DDDAA; BDABA
名词性从句：
1 -10 ABCBA; BBBCD 11-20ABCDC; CDDBA 21-30 DCBBA; ADBCD 31-40 DDBAC; DABAC 41-50 CDABB; CACBD
状语从句：
1-10 CDBCC; DDDCC 11-20 BBAAA; AABAD 21-30 BADBA; DCACA 31-40 DCDBA; DDCCC 41-50 CBCCA; BACCA
从句综合练习：
1-10 DDDBC; ACACD; 11-20 CDBAA; CDDAD
四．非谓语动词与独立主格结构答案
1-10 ACCBA; BCBCA 11-20 A ADAB; ACCBC 21-30 BCDBA; CAADD 31-40 ACABA; DBDDB 41-50 DAADC; AADBA 51-60 AABDC; DDCAC 61-70 BABBD; ABDDC
五．虚拟语气练习答案
1-10 DCBAB; CABBC 11-20 CCCAC; DADAC 21-30 ABDCB; BCCBB 31-40 CACDB; CCDAC
六．强调句与倒装句练习答案
1-10 BBDDA; DDBBA 11-20 BCCDC; CCDCD 21-30 CBAAA; ACBAD 31-40A ACAA; BABCB
七．形容词、副词练习答案
1-10 BABDB；DCBCB 11-20 BACCA；ADCBA 21-30 CBCDB；CBAAC 31-40 AABAC；BCDBA 41-45 ABBCC
八．平行结构答案
1-10: DCACA; AACAA 11-20: BCADD; ABBAC 21-28: ABBAB; DBA
九．主谓一致练习答案
1-10 ADBBD； ADBCB 11-20 CCDAC; BABDC
十．反意疑问句练习答案
1-10 CABCA ; ACBDB 11-20 ACBDA; DBADD 21-30 CABCD;CBBAC 31-40 BCDCA; CACDA
十一. Keys to vocabulary and structures
Vocabulary and structures 1：
1-5 DCADD 6-10 BCCAD 11-15 DCCCB 16-20 BAABD 21-25 DADAC 26-30CDADA 31-35 DDDAA 36-40 ABACC Vocabulary and structures 2：
l-5 CBABD; 6-10 BCBCA 11-15 CDDAC; 16-20 BCADD 21-25 BCADA; 26-30 CDABD Vocabulary and Structures 3：
1-10 CCBBC; DDACB 11-20 CCCAD; DBBAA 21-30 BAAAC; DCBBA Vocabulary and Structures 4：
1-5 BDCAD 6-10CBBCB 11-15 AAADC 16-20AAACA 21-25ADD CB 26-30ADBDA 31-35CCADD 36-40 BBCAC Vocabulary and Structures 5：
1-5 BBDAC 6-10CABDC 11-15 BAADA 16-20ADCDD 21-25 BDACB 26-30 DCCAD 31-35 BADBB 36-40ADBDB Vocabulary and Structures 6：
1-5 ACDBD 6-10 BACBD 11-15 BABCD 16-20 CBCCC 21-22 AA Vocabulary and Structures 7：