形容词bad,如果后面跟名词或者代词,其用法主要是be bad for sth / sb;如果要接动词或者动词短语,可以说be bad for doing sth或者用不定式 be bad to do,后者更常见。
请看例句:
It is a bad time for buying a house.
It is a bad time to buy a house. (用动词不定式也可以)
现在是不适宜于购置房产的时期。
This beach is good for swimming but bad for surfing.
这片海滩适宜游泳而不适合作冲浪运动。