USES OF THE INFINITIVE (A Practical English Grammar, Thomson/Martinet)
The infinitive can be used alone or as a part of an infinitive phrase.
The infinitive may be the subject of a sentence.
The infinitive can be the complement of a verb.
The infinitive can be the object or a part of the object of a verb. It can follow the verb directly or follow verb+ how, what, etc. or follow verb + object.
be + infinitive can express commands or instructions
The infinitive can express purpose.
The infinitive can be used after certain adjectives.
The infinitive can connect two clauses.
The infinitive can sometimes replace relative clauses.
The infinitive can be used after certain nouns.
The infinitive can be used with too/enough and certain adjectives/adverbs.
An infinitive phrase such as to tell the truth, to cut a long story short can be placed at the beginning or end of a sentence.
The continuous infinitive.
The perfect infinitive.
The perfect infinitive continuous.
GERUND - FORM AND USE (A Practical English Grammar, Thomson/Martinet)
As subject of a sentence.
As complement of a verb.
after prepositions.
after certain verbs.
in noun compounds.
The perfect gerund.
The passive gerund.