A．issueB．troubleC．thingD．matter
A. issue
B. trouble
C. thing
D. matter
查看答案
Spammers use software to guess at email addresses.
A. YES
B. NO
【B16】
A. In return
B. And
C. Instead
D. Returning
Legal permanent residents dare not enroll their children in medical insurance, because they are afraid this may become a barrier to ______.
A. their application for citizenship
B. their participation in activities
C. their admission to university
D. their enjoyment of welfare
A．atB．byC．inD．on
A. at
B. by
C. in
D. on
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