The phrase "a horrendous time" is correct and usable in written English.
It can be used to describe a very unpleasant or difficult experience someone has gone through.
Example: "During the storm, we had a horrendous time trying to find shelter and stay safe."
Alternatives: "a terrible time" or "an awful time".
"We had a horrendous time," he said.
"Somerset residents have been facing a horrendous time since before Christmas, yet all they have had from ministers is government by PR.
As if that were not enough horror for this utterly decent family, his father then met a ghastly death by falling into a vat of boiling water, yet all Blunkett offers is the unbelievably trite statement that this "was a horrendous time in my life, a time I shall never forget".
No, not a mistake, because he was in the middle of a terrible marriage that he should never have got into – he had a horrendous time with the Mandy girl – and he then married a very good woman and had three children very quickly … and he was very, very happy.
I'm having a horrendous time.
It was such a horrendous time".
"I don't go on too much about it but we've had an horrendous time of it.
Perhaps, to give him the benefit of the doubt, he was just trying to put on a front in what must have been a pretty horrendous time for Crewe.
"Our thoughts go to the family and friends of these tragic victims during what can only be a quite horrendous time for them.
(Wow. Best metaphor ever!) And that meat is this: While there's no question that Father No Communion For You! picked a spectacularly horrendous time to bare his bigoted fangs, he is also the sole villainous Catholic in a story starring a great many Catholic heroes.
"It was an absolutely horrendous time, I'll never get over it because it nearly cost me everything," he said.
