Genesis 4:1 states:
וְהָאָדָם, יָדַע אֶת-חַוָּה אִשְׁתּוֹ; וַתַּהַר, וַתֵּלֶד אֶת-קַיִן, וַתֹּאמֶר, קָנִיתִי אִישׁ אֶת-יְהוָה.
And Adam knew (אֶת־) Eve his wife; and she conceived, and bare (אֶת־) Cain, and said, I have gotten a man from (אֶת־) the Lord. (Genesis 4:1 KJV)
The same word appears to be repeated. The first and second times it is not translated, the third time it is. In addition the two are treated as a different word, as Strong's #853 and #854.
What is the difference between the two?