Prepositional Phrases

Identify the prepositional phrase in the following sentence. "The Mississippi River flows towards the south."

Identify the prepositional phrase in the following sentence. "Some supplies fell into the water."

Identify the prepositional phrase in the following sentence. "Other boats were parked near the shore."

Identify the prepositional phrase in the following sentence. "We pulled the oars through the muddy water."

What part of speech is the first word of a prepositional phrase?

Identify the prepositional phrases:

The dog hid underneath the couch during the thunderstorm.

Which sentence uses the bold word as a preposition?