[单项选择]Written application should be sent to us in case ______ something wrong with the electric version.
A. there be
B. there will be
C. there is
D. there was

[简答题]

Samples：The approval samples must be sent to us within 7 days after the order is confirmed.

[单项选择]Which is not sent by the US military
A. Amy
B. Ships.
C. Planes.
D. Personnel.

[单项选择]The explosion sent us ______ in all directions.
A. run
B. running
C. to run
D. ran

[填空题]They sent us their statement, (hope) ______ to get our support.

[简答题]if in case unless until when

The filter should be changed ______ the unit has been in operation for two months.

[简答题]if in case unless until when

The machine should not be modified ______ a service engineer is present.

[单项选择]
One useful anti-cancer drug can effectively erase the whorls(萝状指纹)and other characteristic marks that give people their distinctive fingerprints．Losing them could become troublesome．A case (51) online in a letter by Annals of Oncology indicates how big a (52) losing finger prints is．
Eng-Huat Tan，a Singapore-based medical doctor describes a 62-year-old man who has used capecitabine(卡培他滨)to (53) his nasopharyngeal cancer(鼻咽症)．After three years on the (54) ，the patient decided to visit his U．S．relatives last December．But he was stopped by U．S． customs officials (55) 4 hours after entering the country when those officials couldn’t get finger prints from the man．There were no (56) swirly(旋涡状的)marks appearing from his index fin ger．
U．S．customs has been fingerprinting incoming foreign visitors for years，Tan says．Unfortunately， for the Singaporean
A. diet
B. exercise
C. recovery
D. drug