adv, used in rhetorical questions
how could (one possibly); how is (it possible) (syn.) 哪能, 甲通, 安能, 豈可, 岂能, 豈能, 岂可
他是主管，説話怎能不作準？
他是主管，说话怎能不作准？
tā shì zhǔ guǎn ， shuō huà zěn néng bù zuò zhǔn ？ He is the boss, how can his words not matter?
Examples (Tatoeba—Mandarin-English)
Mandarin
我怎能忘记那些日子呢？
我怎能忘記那些日子呢？
wǒ zěn néng wàng jì nà xiē rì zi ne ？
How can I forget those days?
Examples (Wiktionary)
Mandarin
过了些日子，那几个受过高等教育的年轻人知道了强的底细，心里就起毛说，就凭我们的学历，怎能窝在他手下？
過了些日子，那幾個受過高等教育的年輕人知道了強的底細，心裏就起毛説，就憑我們的學歷，怎能窩在他手下？
guò le xiē rì zi ， nà jǐ ge shòu guò gāo děng jiào yù de nián qīng rén zhī dào le qiáng de dǐ xì ， xīn lǐ jiù qǐ máo shuō ， jiù píng wǒ men de xué lì ， zěn néng wō zài tā shǒu xià ？
After a few days, those few youngsters who had received higher education learned of Qiang's background, so they felt disconcerted and said, "On the basis of our educational background, how could we stay under him?"