Past Simple Passive vs Past Simple with 'follow'

Question

Here is an extract from my grammar practice book.

A young man was walking through a supermarket. Suddenly he noticed that he (follow) by an old lady.

As far as I understand, in that situation we should use Past Simple for short and Past Continuous for long actions. The man from the example is being followed, thus we must use Passive Voice.

So, here we have

A young man was walking through a supermarket. Suddenly he noticed that he was being followed by an old lady.

Is it correct?

I kindly ask you to clarify it because the key says was followed.

Thank you in advance:)

Answer 1

It is possible to say "was followed" or "was being followed" in this case.

Both are passive ('to be' + past participle). The difference is the aspect being used.

1. "Was followed" is passive simple past.
2. "Was being followed" is passive past progressive. (to be + to be present participle + verb)

Either is natural in this example. The fact that the young man was followed in an ongoing manner, which is what the progressive aspect conveys explicitly, is conveyed implicitly in the case of the simple past.