我打不通电话—线路忙。

I couldn't get through—the line's engaged.

《牛津词典》

我打不通电话线路一定出故障了。

I can not get through — the lines must be crossed.

youdao

我打不通电话。

I can't get through.

youdao

我打不通电话。

I can't get through.

youdao