First of all you need to stop using Internet slang and abbreviations when you write your essay.  It cheapens your writing and you will never able to master the language at all.

So Difficult To Remember So Much.

I am quite frustrated with these idioms.  How can I remember so many of them.  For example, "get at somebody" means to "get revenge" or "blow something up" means "to explode".  All these idioms make me feel giddy.  Goodness gracious!  Who can help me.

No one except yourself in memorizing these.  The difficulty lies in not having lots of chances to practise.  No practice and soon you mind will forget them.  If you can memorize 5,000 Chinese characters, I don't think that's a problem with your brain.  You have to use them everyday.  Well Chinese too have its share of idioms.

It's so difficult to remember such a quantities of phrase verb

I am disturbed by these irregular phrase verbs! How can I remember so many of it,for example,"get at sb"means"to criticise some one all the time and upset them",and"blow sth. up" means"to use a bomb to destory sth" It's really make me giddy . Oh god, who can help me!