Englishfor English speakers
a
Determinative
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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
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A is the first letter of the alphabet.
The letter "a" comes before "b".
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In some schools, an A is a very high grade.
Ron got an A on his earth science test.
variety
Noun
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A variety of things is a group of things that are not all the same.
Americans can buy a wide variety of cheap products at local supermarkets.
This study was conducted over a relatively long period of time and in a variety of settings.
The films cover a wide variety of topics from wars to fantasy.
The teachers use a variety of techniques to help the students understand the material.
We get the information from newspapers and a variety of other sources.
They felt it was important for a variety of reasons.
The shirts are available in a variety of fun colors.
Middle school students participated in a wide variety of activities.
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Variety is the quality of not being the same.
Fruit can add variety to your salads.
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A variety is one kind of something, especially plants and animals.
The shop has 25 tomato varieties.
By 1930, Southerners alone had developed nearly 1,400 unique apple varieties.
of
Preposition
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Made using.
It is a house of cards.
effector
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noun
an organ (a gland or muscle) that becomes active in response to nerve impulses
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noun
a nerve fiber that terminates on a muscle or gland and stimulates contraction or secretion
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noun
(= effecter)
one who brings about a result or event; one who accomplishes a purpose
mechanism
Noun
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A mechanism is the way something works
This research should help us to understand the mechanisms of memory.
This agreement sets out detailed mechanisms for solving disagreement between the two countries.
These two features combine to create a new data retrieval mechanism.
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A mechanism is one moving system within a larger, more complex machine or organism.
The body has a control mechanism to bring down blood-sugar level when it begins to reach unhealthy peaks.