What did they look?=How did they like?还是=How did they look?

你这几个句子应该是存在语病的,look通常情况下作不及物动词,后面需接at,like等介词
1.如果是表达看的意思,句子可改成what were they looking at?
2.如果是表达“像”“如同”的意思,可改为：
how did(do) they look like?.怎么样?比如how do you like china(你觉得中国怎么样?）
how did(do) they look?...看上去.怎么样?
What did(do) they look like?它看起来像什么?