兩者表達的意思不一樣，What about是用來詢問與前一個事物相關的另一個事物的狀態；而How about是用來徵求別人的意見，問別人是否能夠接受另一個選擇。What about後面用跟名詞的多；而How about後面跟動詞現在分詞多。
What about的例句
1、What about going out with me tomorrow?
明天和我一起出去怎麼樣？
2、What about my copier? Can you get it going again?
我的複印機怎麼樣了？你能把它修好嗎？
3、You are all going. What about me?
你們都去，我呢？
How about的例句
Are your products and services competitive? How about marketing?
你們的產品和服務有競爭力嗎？營銷又怎麼樣呢？
Well, I enjoyed that. How about you two?
嗯，我覺得那很棒。你們倆呢？
You want Jeannie to make the appointment for you? How about the end of nextweek?
你想讓珍妮幫你預約嗎？下週末怎麼樣？
兩者通用的情況舉例
在表達提出某種建議的意思，比如...怎麼樣；...好嗎？時，How about和 What about是可以互換的，即意思是一樣的：
How/What about a drink?
喝杯酒怎麼樣？；喝杯酒好嗎？
Where should we go on vacation?
How about Hawaii?
What about Japan?
我們該去那裏度假呢？
去夏威夷怎麼樣？
去日本好嗎？
