Questions & Answers about Mein Ziel ist es, mein Deutsch zu verbessern.
Why does zu verbessern go at the very end of the sentence?
In an infinitive clause (a sentence part using 'to do something'), the zu + infinitive verb must always go at the very end. Here, the action is improving your German, so mein Deutsch comes first, followed by the verb zu verbessern.
Why is there an es after ist? Doesn't that mean 'My goal is it to improve my German'?
Exactly! In German, it is very common to use es as a placeholder in the main sentence to point forward to the zu-clause that follows. While you can sometimes drop it, saying Mein Ziel ist es... sounds very natural in German, even though we skip the 'it' in English.
Why is it mein Deutsch and not meinen Deutsch?
The word Deutsch (the German language) is a neuter noun (das Deutsch). Because it is the direct object in this clause (the thing being improved), it is in the accusative case. For neuter nouns in the accusative case, the possessive word is simply mein.
Do I really need that comma before the zu clause?
Yes, in this specific sentence you do. When a zu-clause is announced by a placeholder word like es in the main sentence, German grammar rules require a comma to separate the two parts.