I Really Need Your Help

Hello, dear users. I've come here looking for help. To make it easier for you to understand what I need I'm going to tell you a short story. I'm a Russian teenager, who's desperately in love with the English language. Since I'm in the 10th grade (well, almost) and there're 2 years left until the most important exam in my life, I need to start preparing for it as soon as possible. But it's not the main problem (actually, it's not a problem at all). I want to become an interpreter and study at the most prestigious university in Moscow. To make it real I need to take part in various Olympiads. That's where things become complicated. The problem is that you never know what to prepare for. But I know exactly that olympiad tasks are very tricky. Here's an example:

You need to reformulate the following sentence:

You mustn't park your car next to the sidewalks

To reformulate the sentence you need to use the following expression - under no circumstances.

Under no circumstances should you park your car next to the sidewalks.

Well, in this case I'd like to know whether there're any books that review this kind of aspect of the English language (phrasal equivalents). If it doesn't trouble, I'd like to know more: tricky grammar rules, the usage of prepositions in different situations (I hope you understand that I don't imply the usage of prepositions on/in/at, etc.). I'm out of ideas. So, please, if something that I'm asking for comes to your mind, let me know. Thank you in advance.

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If you spot any grammar mistakes in this post, feel free to correct me.