I don’t know _____ (how / why) so many people are looking at him.
句意：我不知道为什么有那么人在看他。该句是由“why 为什么”引导的宾语从句，“how 怎么”不符合句意，故答案为 why。
2018年12月，张阿姨把4000元的存入银行，定期三年，年利率是2.75%到期后，应得利息______元.
I don’t know _____ (how / why) so many people are looking at him.
They don’t know _____ (if / whether) to go or wait.
I really don’t know _____ (how much / how soon) the bridge will be finished.
She said _____ (that / if) it wouldn’t matter much.
The prices of the vegetables in this market are very _____ (high / expensive).
—I hate rainy days. —_____ (So do I / So I do).
He isn’t going to have the concert tonight, _____ (isn’t he / is he)?
It’s going to rain, _____ (isn’t it / is it)?
—Have you been to this school? —No, _____ (I haven’t / I didn’t).
