Englishfor English speakers
of
Preposition
—
Made using.
It is a house of cards.
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.
duration
Noun
—
The time something takes, or how much time it takes.
In the duration of his speech, ten more people came into the room
The duration of this event will be three hours.
For the duration of the work painting the rooms, you'll have to sleep in a different room.