Different languages have different ways of expressing things. It is difficult to translate things exactly the same between two languages. Sometimes words have multiple meanings. Some language have very dense construction, while others require many words to say the same point. Grammar and structure differ. Some language have gender, while others do not. Two words may have similar origins in different languages but gradually evolved to have different nuances. It all makes a challenge translating, with the best hope usually a close approximation of the original.
Languages are always changing and evolving. Identifying a "proper" or "correct" version of the language is not nearly as important as understanding. Purists have made efforts to look at the true "original" meaning of words, but these may not bear relevancy to what it means today. (The word decimate was given as an example. It was related to a tenth, but now means destruction.) Language is changing, not necessarily getting better or worse.
The book spends a while discussing Chomsky and universal grammar. Then a lot of time is spent refuting Chomsky's arguments. There is some interesting ways of looking at language as a whole, but it does get fairly erudite. There seemed to be a lot of this that I had seen before.
People in colonial East Africa lived their lives. There were German troops that tried to enforce a colonial presence. While these changed some of the details about how lives were lived, they were also people. The Africans lived their lives as best they good. There were some conflicts between German instruction and African customs, but people remained people. The Africans did observe the switch from German to English. However, the details of this were more of a far away influence. Later there were opportunities to go to Germany and further study as part of the "decolonization" efforts of the Germans after World War II. Africans served in the German military. Africans also deserted the military. They had contacts in Germany as well as family living there. The colonial experience caused plenty of changes in the what and the where, but only a little in the who. They had some interactions with colonializers, but most remained with their close family and friends.