What method can you see the lexical nature of words?You can see it if you use it. Pay attention to the way it is used to the words.
Let us take an example of the word"level";eg:-level---noun, adj, verb
level noun;eg:-
Profits were at the same level as the year before covid19------n.
The war discussion congress are currently being held at national level.-----n
The floodwater nearly reached roof level in the country.-----n
Archaeologists found pottery in the lowest level of the (xxx) site.-----n
As adjective--level; eg:-
The government pay rise is intended to keep wages level with inflation.----adj
As verb---level; eg:-
The bomb blast levelled several buildings in the area.----v
Workers are laying tiles and the floor will need to be levelled first.-----v