Polysemous

1- how can we recognize polysemous words?

2- Is there any rules for translating polysemous words?

3-how can we choose the best meaning for polysemous words?

No. Polysemotism is the characterisic of having many meanings, thus, both lay and lays are each mildly polysemous. BTW, the most polysemous word in English is 'set', with more than 20 meanings.

The English letter "g" is polysemous, because it can make a hard sound like in "good" or a soft sound like in "giant". In the word "gauge" it make both sounds.

a homophone