你学中文学了多长时间？
nǐ xué zhōngwén xué le duōchángshíjiān ？
How long have you been learning Chinese?
从这里到机场要多长时间？
cóng zhèlǐ dào jīchǎng yào duōchángshíjiān ？
How long does it take to get from here to the airport?
你每天睡多长时间？
nǐ měitiān shuì duōchángshíjiān ？
How long do you sleep each day?