Englishfor English speakers
that's
pronoun
—
(rare, nonstandard) whose, of which
a
Determinative
—
A is used when the following word could be any of a certain type.
Compare "A book I saw on the shelf" and "The book I gave you yesterday".
a
Noun
—
A is the first letter of the alphabet.
The letter "a" comes before "b".
—
In some schools, an A is a very high grade.
Ron got an A on his earth science test.
comfortable
Adjective
—
If a piece of furniture, clothing, a room, etc. is comfortable, you feel comfortable in it (see 2.)
There were a few old but comfortable chairs in the meeting area.
—
If you feel comfortable, you are not hot or cold; you are relaxed, and you feel no pain or worry.
The nurse put a blanket on me to make me more comfortable.
She doesn't feel comfortable with a dog in the house.
sofa
Noun
—
A sofa is a type of chair with soft seats and arm rests, typically designed to seat more than one person.
Your sofa is comfortable.