When you express your apologies to your guest you may say "I beg you pardon, sir" in rising tone.
查看答案
When you ask the guest to repeat what he says you may say "I beg you pardon, sir" in rising tone.
A. 对
B. 错
When you don't understand what the guest says and ask the guest to repeat you may say
A. Pardon, please. I'm afraid I didn't follow you.
B. Would you mind repeating a little more slowly?
C. I beg your pardon?
D. Would you mind using simpler words?
合成RNA的原料是:
A. NMP
B. NDP
C. NTP
D. dNTP
E. dNDP
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