English grammar confusion

"The HK productivity council revealed a survey showed 90 percent of users accept apps."
= The HK productivity council revealed(that) a survey showed(that) 90 percent of users accept apps."

Explaination: This is a complex sentence with 3 parts: Main clause + noun clause + noun clause;in which two relative pronouns "that" are left out.
i) The HK productivity council revealed (v) something (that-clause)
ii) A reveal showed (v) something (that-clause)
iii) 90% of users accept (v) apps.

There are two sentences:

1. The HK productivity council revealed a survey.
2. The survey showed (that) 90 percent of users accept apps.

It can be written like this:

The HK productivity council revealed a survey, which showed that 90 percent of users accept apps.

Is it three verbs --reveal,show and accept in the same sentence?

Yes, there are three verbs.

i guess there is a (that)before the "showed" .is it ture?

Yes, you should put the word that or which before it. I think "which" is more formal than "that".

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