·Adding information without repeating the sentence
Relative clauses and participles. Relative clauses let you add information about a person or thing without starting another sentence, and participles let you shorten them. We will look at the difference between defining and non-defining clauses, the role of whose, whom and which referring to a whole clause, reduced relative clauses and participles at the start of a sentence, like having finished. The rules are AptisBot's own reading.
1/4Defining and non-defining clauses
A defining relative clause tells you which one: the man who lives next door. Without it, you do not know which man is meant. It takes no commas, and you can use who, which or that. A non-defining clause adds an extra detail about something already clear: my brother, who lives in Madrid, is a doctor. It goes between commas, and you cannot use that. Notice: without commas, my brother who lives in Madrid suggests you have more than one brother. Use who for people, which or that for things. And when the relative pronoun is the object, it can be left out in a defining clause: the book I bought.
2/4Whose, whom and which for a whole clause
Three more relative pronouns. Whose shows possession, with people and also with things: the woman whose car was stolen. Whom is the formal object form and usually follows a preposition: the person to whom I spoke. And which can refer to the whole previous clause, not just one word, and always follows a comma: he passed the exam, which surprised everyone. Here which does not replace exam, but the whole idea that he passed. And be careful: with a preposition in front, the relative pronoun is whom or which, never who or that.
3/4Reduced relative clauses
Reduced relative clauses shorten the sentence. If the relative pronoun is the subject, you can drop it together with the verb be: the man who is sitting there becomes the man sitting there. With the passive: the book that was written by Orwell becomes the book written by Orwell. And with a verb other than be, you use ing: a law which prohibits smoking becomes a law prohibiting smoking. You can only reduce when the relative pronoun is the subject. If it is the object, you do not reduce it: the book that I bought does not become the book buying.
4/4Participles at the start of a sentence
Participles can also open a sentence and replace a clause of reason or time. With ing, when two actions happen at the same time, or one explains the other: walking home, I met an old friend. With having plus a past participle, when one action happened before another: having finished the report, she went home. And with the past participle, for a passive meaning: written in 1990, the book is still popular. The key rule: the person doing the participle's action must be the subject of the main clause. Walking home, the rain started is a mistake: the rain was not walking.
·Practice
For practice, write four sentences about someone you know. One with a non-defining relative clause, between commas. One with whose. One with a reduced relative clause, like the man sitting. And one that begins with having and a participle. Then check whether the person doing the participle's action is the subject of the main clause.