Although the Israelites were slaves for 400 years and in the land of Egypt for a total of 430 years, they never took the time to learn the Egyptian language.
By the time the 10th plague (the killing of the firstborn child - of which every single household of the land of Egypt had a child die) the Egyptians begged the Israelites to leave. They feared them greatly. In verses 3-6 the elements of the earth (the sea, the River Jordan, the mountains, and the hills) also appear to have feared the presence of the Lord. Verse 7 reminds us that we each should have a reverential fear of God (not be afraid of Him - but be in awe of Him, and who He is - and what He had done in each of our lives). Finally, in verse 8 we are reminded that - not only did God deliver the Israelites from Egyptian bondage, but He also provided for them when they were in the wilderness for 40 years - providing food for the (the manna from heaven - but also water from a rock.