Identify the type of non-finite verb underlined in the following sentence.

He tried to warn her before leaving.

The correct answer is option 1, i.e. Infinitive.

Key Points

• A verb which is not limited to person and number and does not show any tense is called a Non-finite verb.
• A non-finite verb does not act as a verb.
• There are three types of non-finite verb: gerunds, infinitives, and participles.

1. A gerund is a verb that acts as a noun. It is an '-ing' verb. E.g. "Reading is her hobby."
2. Infinitives are the basic form of a verb(to+verb) and these are mainly non-inflected verb. Infinitives can be used as adverbs, nouns or adjectives. E.g. "They planned to visit my place much before." Examples of infinitives include to read, to run, to jump, to play, to sing, to laugh, to cry, to eat, and to go. 
3. Participles are the verbs ending in 'ed' and 'ing', and which act as adjectives. E.g. "I found a boy dancing in the middle of the road."