200 English Grammar Mistakes!: A workbook of Common Grammar and Punctuation Errors with Examples, Exercises and Solutions So You Never Make Them Again

Even
though he made $400 million
, he remains grounded
," 
the highlighted part is
the  dependent  clause.  Below  are  some  common  errors  associated  with
clauses:
A defining subordinate clause should be introduced with “that,” not “which."
Incorrect:  The river 
which
 flows through Lisbon is murky.
Correct: 
The river 
that
 flows through Lisbon is murky.
A  non-defining  subordinate  clause  should  be  introduced  with  “which”  not
“that” while being separated with two commas.
Incorrect:  The Nigerian river Benue, 
that
 flows through Niger, is murky
and turbid.
Correct: 
The Nigerian river Benue, 
which
 flows through Niger, is murky
and turbid.
A defining subordinate clause should be introduced with “who,” not “whose."
Incorrect:  The American military officer 
whose 
defeated the Italians
became the president.
Correct: 
The American military officer 
who 
defeated the Italians became
the president.
A  non-defining  subordinate  clause  should  be  introduced  with  “whose,”  not
“who” while being separated with two commas.
Incorrect:  The King of England
, who
 kingship was the reward for his
heroics, was an unusual man.
Correct: 
The King of England
, whose
 kingship was the reward for his
heroics, was an unusual man.

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