be bad for后面加什么形式

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。