"I will remove the names of the Baals from her lips; no longer will their names be invoked." NIV translation
In the Day of the Lord, all of the false gods and idolatry will be removed. This has not happened yet as we know that, today more than ever before, people have made so many things their master (Baal).
"In that day I will make a covenant for them with the beasts of the field and the birds of the air and the creatures that move along the ground. Bow and sword and battle I will abolish from the land, so that all may lie down in safety." NIV translation
Peace is going to come to the earth but not without the Prince of Peace which is Jesus. This verse has not been fulfilled yet as there has never been a time when there was absolute peace on the earth since sin came into the world. This peace is going to include the animals as well as all peoples on the earth.
"I will betroth you to me forever; I will betroth you in righteousness and justice, in love and compassion. I will betroth you in faithfulness, and you will acknowledge the Lord." NIV translation
We will be married to God and it will be for eternity because God doesn't do divorce. It is interesting to note here that God kind of gives us a marriage contract where he does most of the work and we simply "acknowledge the Lord". As we see, in 1 John 4, this means that we accept that Jesus is the Son of God and not just a good man or prophet.
"'In that day I will respond,' declares the Lord - 'I will respond to the skies, and they will respond to the earth; and the earth will respond to the grain, the new wine and oil, and they will respond to Jezreel.'" NIV translation
On the Day of the Lord, everything will be made new as there will no longer be sin and its effects on the earth. God will once again supply the needs of His people just as He did with Adam and Eve in Eden. This is also described in Revelation 21.
"'I will plant her for myself in the land; I will show my love to the one I called "Not my loved one." I will say to those called "Not my people" "You are my people"; and they will say, "You are my God."'" NIV translation
When the people repent, God is faithful and just to restore them to fellowship. God called them to repentance (back to the land) and when they did, He demonstrated His love by forgiving them. The same is true for us today.