Herein, Therein, Hereafter, Thereafter

Herein

neste lugar,  aqui contido, anexo, aqui (neste texto, neste documento)

“For an explanation of the abbreviations used herein, see the section entitled ‘Abbreviations in this Work.” (www.merriam-webster.com)

"I shall discuss the question herein"(www.thefreedictionary.com)

Therein

nisso, naquilo, naquele lugar, na sequência, nesse sentido, dessa maneira,  nesse ponto, naquela circunstância

"They can read therein what our plans are" (www.thefreedictionary.com)

“The insurance covers the apartment and all the property therein.”

“His name was mentioned in the article, although he was incorrectly described therein as a medical doctor.” (www.merriam-webster.com)

Hereafter

depois, daqui por diante, futuramente, a partir daqui

“Hereafter the two companies will operate in full partnership.’

“We don't know what will happen hereafter.” (www.merriam-webster.com)

Thereafter

depois disso, depois, a partir daí, conseqüentemente, de acordo com isso

“Thereafter, the two companies operated in full partnership.”

“…gave his farewell speech and left the room shortly thereafter…”  (www.merriam-webster.com)

More interesting facts about English

1.We can find 10 words in the 7-letter word "therein" without rearranging any of its letters: the, there, he, in, rein, her, here, ere, therein, herein.

2.The "QWERTY keyboard" gains its name from the fact that its first 6 letter keys are Q, W, E, R, T and Y. On early typewriters the keys were arranged in such a way as to minimize the clashing of the mechanical rods that carried the letters. (www.englishclub.com)