题干
-With the help of the new technology（技术），you ___________ e-mail your friends by mobile phone.
A：can
B：must
C：need
D：should
答案(点此获取答案解析）
A
-With the help of the new technology（技术），you ___________ e-mail your friends by mobile phone.
A：can
B：must
C：need
D：should
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