if the occasion arises

i'll buy one if the occasion arises.

如果有机会我就会买一个。

you should change your job if the occasion arises.

如果有合适的机会你应该换换工作。

i'll change my job if the occasion arises.

有机会时我会换个工作。

I'll speak to him about it if the occasion arises (= if I get a chance).

有机会的话，我要跟他谈谈这件事。

I'm willing to go to court over this if the occasion arises.

如果必要的话，我愿意就此出庭。

I will write and let you know if the occasion arises.

必要时我会写信告诉你的.

you should go there if the occasion arises.

如有机会，你应该到那里去。

i will speak to him if the occasion arises .

如果有机会我将跟他说。

i shall tell her what i think if the occasion arises.

待有合适的时机，我会把我的想法告诉她。

I'm willing to go to court over this if the occasion arises (= if it becomes necessary) .

如果必要的话，我愿意就此出庭。