Gerund vs. infinitive

Numerous exercises on gerund vs. infinitive along with their key are hereby made available for you to have access at your convenience.  You can also find the list of verbs used with gerund and/or infinitive here.

Here you can find more information and exercises on the same topic.

How to Write Clearly

Here you can find the Commission guide entitled "How to Write Clearly".

Some sites recommeded by Katja

Here are some links Katja was kind enough to send me:

Grammar exercises: 
http://www.englishgrammarsecrets.com


Listening comprehension:
http://www.bbc.co.uk/worldservice/learningenglish/general/sixminute

I think this might be a bit too easy for your level.

A list of words with prepositions:
http://www.stage-door.org/stampact/preps.html

Thank you Katja!

Prepositions

Basic prepositions:
Here you can find some exercises on basic prepositions.  The key to the exercises is hereby made available. (Source: English Grammar in Use: Intermediate by Raymond Murphy) 

Noun, adjective and verb + preposition:
Here you can find some exercises on nouns, adjectives and verbs which are used with certain prepositions.  The key for the exercises are also hereby made available. (Source: English Grammar in Use: Intermediate by Raymond Murphy)

Phrasal verbs:
Here you can find some exercises on phrasal verbs.  The key to the exercises is hereby made available. (Source: English Grammar in Use: Intermediate by Raymond Murphy) 

Tenses and key words

Here you can find many exercises on tenses.  I am also hereby making a list of all the tenses and key words available.

False friends for French

Here you can find a list of false between French and English.

Semicolon, colon and lists

In Sections  2.5 - 2.10 of the English Style Guide published by the Directorate-General for Translation, you can find the rules on the use of colon and semicolon with the appropriate hyperlinks for other relevant issues, such as lists.

You can hereby find more information on the use of colon and semicolon as well as providing lists as it is presented in the Interinstitutional Style Guide.

Here you can find a document on the use of semicolon and colon, including the use of the latter to introduce lists.  The first rule on the use of colon in this document is at odds with what is said in the Commission's "English Style Guide" and  the "Interinstitutional Style Guide".

Here you can find a quiz on the use of colon and semicolon with the key and explanations.  In the explanation for the answer to question 21, you can find the capitalization rule in sentences after colon.