Phrase versus clause

This is a phrase:
in the hat
This is not a phrase:
hat the in

This is a phrase (not a clause):
Rex the dog
This is a clause:
Rex barked

The easiest type of clause to identify has a stated subject and a predicate:
Rex [SUBJECT] || barked [PREDICATE].
Rex [SUBJECT] || barked at the cat [PREDICATE].
(“Barked” is the verb. “Barked at the cat” is the complete predicate. The predicate includes the verb.)
Rex the dog [SUBJECT] || barked at the cat [PREDICATE].
(“Rex the dog” is the complete subject. “Barked at the cat” is the complete predicate.)

A phrase does not have the subject-predicate structure of a clause: 
on the boat
in the classroom
would have been
stand up

NoteIn everyday language the term “phrase” refers to two or more “grammatically related” words. (“the big dog” not “dog big the”) Grammarians, however, also use the word “phrase” to apply to just one word because a single word can serve the same function as a phrase:

Sentence Verb phrase
Rex is barking. is barking
Rex barked. barked
   
Sentence Noun phrase
Rex barked. Rex
Rex the neighbor dog barked. Rex the neighbor dog

James Thurber’s country mouse

The Mouse Who Went to the Country
By James Thurber

Once upon a Sunday there was a city mouse who went to visit a country mouse. He hid away on a train the country mouse had told him to take, only to find that on Sundays it did not stop at Beddington. Hence the city mouse could not get off at Beddington and catch a bus for Sibert’s Junction, where he was to be met by the country mouse. The city mouse, in fact, was carried on to Middleburg, where he waited three hours for a train to take him back. When he got back to Beddington he found that the last bus for Sibert’s Junction had just left, so he ran and he ran and he ran and he finally caught the bus and crept aboard, only to find that it was not the bus for Sibert’s Junction at all, but was going in the opposite direction through Pell’s Hollow and Grumm to a place called Wimberby. When the bus finally stopped, the city mouse got out into a heavy rain and found that there were no more buses that night going anywhere. “To the hell with it,” said the city mouse, and he walked back to the city.

Moral: Stay where you are, you’re sitting pretty.

Thurber, James. The Mouse Who Went to the Country. In James Thurber, Fables for Our Time and Famous Poems Illustrated. Garden City, NY: Blue Ribbon Books, 1943. Print. (3).

A terrific ‘zoonoses’ sentence

[Pronunciation: zoh-onuh-sis, zoh-uhnoh-sis]

Original:
Infectious diseases that can be transmitted to humans from infected animals are known as zoonoses.

SM’s revision in class today:
Diseases given to humans by animals are called zoonoses.

Much better!

Here it is in context:

Infectious diseases are the only ones that can be transmitted. They may be spread by infected animals, infected people, or contaminated substances, such as food and water. Infectious diseases that can be transmitted to humans from infected animals are known as zoonoses. Diseases given to humans by animals are called zoonosesZoonoses may be transmitted by carriers, such as insects; by the bite of an infected animal; by direct contact with an infected animal or its excretions; or by eating animal products.

Zoonoses are:
a. insects that carry diseases.
b. infected animals that transmit infectious diseases to humans.
c. infectious diseases that man gets from animals.
d. carriers that transmit infectious diseases.

Whimbey, Arthur and Linden, Myra J. Teaching and Learning Grammar: The Prototype-Construction Approach. Chicago: BGF Performance Systems, LLC, 2001. Print. (90-91).