只 zhǐ appropriate use in context?
只得, [be obliged to;have to;have no alternative but to] 别无选择，不得不

我们只得照要求的做了。
Source: http://baike.baidu.com/view/4174590.htm

只好 [be forced to;have to;the only alternative is to] 只有;只能. It is a little less formal than 只得.
河上没有桥,我们只好涉水过去

Source: http://baike.baidu.com/view/163453.htm



只有: only. 邮局离这儿只有几步路。

only when (when followed by 才), to indicate a necessary condition. 
只有依靠群众,才能做好普查工作.
Source: http://baike.baidu.com/view/199454.htm