Prepositions

Prepositions are link words beginning phrases.
They link the trunk of the sentence with: 
the branches of time and/or place + manner + reason - adverbial phrase/s qualifying the verb
+
the descriptive branches - adjectival phrase - qualifying the noun


I read the book - main trunk of the sentence.
about dreams - adjectival phrase qualifying book. 
It begins with the preposition about. 
in the afternoon - adverbial phrase of time qualifying the verb read. 
It begins with the preposition in.
beneath the tree - adverbial phrase of place qualifying the verb read. 
It begins with the preposition beneath.



NOTE

** prepositions are usually monosyllabic - one syllable
+
** Phrases do NOT contain a verb
** A group of 3 words usually = a phrase

+
for a full list of prepositions see
English Grammar 4U Online
(exercises are included)

Adverbs + Adverbial Phrases ~ Specify details of verbs

Adverbs and adverbial phrases qualify verbs.
They add colour and interest to the action in a sentence.

1. Adverb - One word qualifies a verb. Most adverbs end in "-ly".
2. Adverbial phrase involves two or more words qualifying the verb.

The phrase may involve:

two adverbs e.g. quite fast

OR

begin with a preposition

at the station - adverbial phrase of place beginning with the prepositon at.
3. Adverbs and adverbial phrases answer:
how - most adverbs answer this question
when
where
why
e.g. In the Winter, many surfers enjoy riding the chilly waves with excitement.
In the Winter - adverbial phrase of time
with excitement - adverbial phrase of manner
NOTE: chilly ends in "-ly" but look at this word's position in the sentence.
It is an adjective describing waves.
(And waves is not automatically a verb. Here it is a noun.)
Before identifying a word's role in a sentence, check where it is in the sentence.
In other words, check the context.