迄今为止英语怎么说

So far、啊

迄今为止
heretofore
so far
up to now
until now
as yet

迄今为止，机器没发生任何故障。
So far it is just a battle of words between the various parties

up to now
so far

until now
so far
to date
例句与用法:
癌症迄今有无有效的治疗方法?
Is there a certain cure for cancer yet?
迄今为止，我从未听说过有人因生活费过昂而不要生存下去的。
So far I haven't heard of anybody who wants stop living on account of the cost.
英国政府对这些报道迄今不予置评.
Downing Street has so far refused to comment on these reports.
科学家们正在作一项迄今为止没人做过的实验。
The scientist is doing experiments no one has so far attempted.

till now
at present
up to now