Answers

2016-08-01T16:58:11+08:00
The objects of a preposition can be either a noun,pronoun,verb,and it should follow the preposition.

Examples:

1-I'm looking for my books 
(prep=for my books=nouns)

2-I'm looking at them
(prep=at them=pronoun)

3-I'm looking forward to going on vacation
(to=prep going=verb)
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