阅读答案：
U1：part1 ACABB DCCAB BCBAB
DADCB CBAB DDCAB
part2 BACAD BACBB DADDA
CDAA DCAA BAD
U2:part1 BBCCB ADBAB BBAAA
CDADD CBABD CBCAB
part2 ADCAB ACABD BDCBD
CCBDB DBABC BACBC
U3:P1 CBCAD BCADC BCBCC BADB BDDCB
P2 DBCBA BCDBC DBABA ACCDA BDBAB CBCC
期中 P1:BCADB BAABB DCDAA ADBBD BADB
P2:BDCAC BDADB CACAC CBC CBD ACADA
U4:P1 ADBDA CADBC CDDCA DABCD DBCAA
P2 ABCAD ACBBC ABCAC DACDB CBCB CSDAD AABB
U5:P1 CADAA DBABA CCBBB DCBCA CCADA
P2 CDBBA BCDAB BACCB ABCDC DCABD CCDCB DCCD
U6:P1 CBAAB DCCCC ABCCC CBCBC CBAAD
P2 ADCCB BDAAC CCCDA DACB ADBDC BDDBC
期末：P1 CBAAC CCABB ADBAC DBACB BCDBD
P2 CCADA CCABA BBABD TFTTF CDCBA CBCAD