Unnecessary prepositions - Grammar short lessons - 2014 -
Sometimes we use prepositions where they are not necessary. While expressions like ‘check up on’ and ‘as from’ are not exactly considered incorrect, they should be avoided in academic and formal writing.
Idiomatic expressions with prepositions -2014 - Grammar short lessons
Verbs often combine with prepositions. These combinations are called phrasal verbs. There are numerous phrasal verbs in English and they cause a great deal of difficulty for ESL students. It is nearly impossible for a non-native speaker to learn all of these idiomatic expressions. Still, you must be familiar with the most important ones.