Safety and security

Safety is a noun. Safety is an adjective.

The landlord's sentence 1: It's () is ambiguous, and the two explanations are as follows:

1a) is very safe. This/it is safe. For example, is raw lettuce safe? Yes, it's safe.

1b) safe. For example, "Why should I wear a helmet?" "Safety comes first." Why should I wear a helmet? Safety comes first.

Actually, 1a) is more commonly used than 1b).

This is a safe place. Here we need adjectives to modify noun places, so we choose safety.

This place is safe. Adjectives are used here as the slogan of is, so it is very safe.

Is that clear?

I have English study Q, and the landlord can add you.