Clauses carry different names for a reason. For example, an independent clause has a subject-verb set and can stand on its own, whereas a subordinate clause, while it also has a subject-verb set, starts with a subordinator (also called a transitional word; Click here) and so cannot stand on its own. For example,

Independent clause: I went to the store.
Subordinate clause: Although I went to the store, ...

Clauses are named according to their function. So, for example, a relative clauses "relates" to a noun; it modifies it, adds more meaning to it; e.g., The man whowants you is over there. Relative clauses begin with a relative pronoun; Click here. Those clauses can be either defining and non-defining:

Defining: A suitcase that has no handles is useless.

If we omit the relative clause that has no handles, the resulting sentence is rendered semantically awkward:

Ex: ?A suitcase is useless.

Defining relative clauses define the noun they modify. Without the clause, the noun loses its meaning.

Here's an example of a non-defining clause:

Non-defining: The car in the garage, which (by the way) belongs to my friend, is fabulous.

Take away the relative clause set in commas and the primary meaning of the sentence stays the same: The car in the garage is fabulous. Non-defining relative clauses are easy to spot: all you have to do is add in "by the way".

The same holds true for adjective clauses and adverb clauses: they're named according to their function.

Azar is a great series. They're fabulous grammarians.

The most common subordinators are:

although, even though,

because, since*, so that,

when, while, before*, after*, whenever,

wherever, anywhere,

if, unless, whether [or not]

as, as [adjective] as,


(to show slight contrast)

(to give reasons)

(to indicate time relationships)

(to indicate place)

(to indicate conditions)

(to give comparisons)

(to show major contrast)

*These words can also be used as prepositions.

Subordinators have an interesting effect on words in a sentence. A clause (S +V) without a subordinator can stand alone as a complete statement.

I went to the store yesterday.

(Complete statement)

However, when a subordinator is added, the statement seems incomplete.

When I went to the store yesterday, . . .

(Well, what happened?)

The subordinating clause becomes dependent on something else to complete its meaning:

When I went to the store yesterday, I saw an old friend.

(Idea is complete)

Subordinating or "dependent" clauses can occur at the beginning or end of a sentence. When used at the beginning of a sentence, a comma is necessary after the clause itself.

S + V although S + V

Although S + V , S + V

In English, the subordinator always comes before the subject and verb in a clause.

I went to the grocery store after, I stopped at the bank.

After I went to the grocery store, I stopped at the bank.



Subordinators and coordinators should not be used in the same sentence to introduce clauses. Choose one or the other, but do not use both together.

Although Nina won the prize, but she was not happy.

Although Nina won the prize, she was not happy.

Nina won the prize, but she was not happy.



(Also correct)

3)-4   接 続 詞

3) 応用: 接続詞についての英語での説明の仕方