We want phrases to describe suspicious not sentence
We say "acting suspicious" to describe someone's behavior or actions that seem questionable or cause concern. On the other hand, "looking suspicious" may refer to someone's appearance that suggests potential wrongdoing, but the more common phrase is "acting suspicious."
Someone or something not suspicious: trustworthy or trusted. Someone not feeling suspicious : trusting, unwary
'Suspicious' is an adjective, it doesn't have a past tense.
The word 'suspicious' can indicate that a person is distrustful or skeptical (e.g. I was suspicious of his intentions), or that a person or situation looks a bit dodgy (His behavior was suspicious).
The synonym for "not suspicious" is "trustworthy" or "reliable."
'Suspicious' .
suspiciously
Suspicious characters do a lot of lurking about...
To stop making yourself seem suspicious, don't do anything suspicious.
The noun form of suspicious is 'suspicion'.
The investigator was extremely suspicious of the suspect's alibi. The suspicious wife followed her husband when he left work.