Phrasal verbs with DOWN, their meanings and examples.
DOWN is a preposition opposite of UP.

Gerund is a word that is formed with a verb but act as a noun. 

To spot gerunds in sentences, just look for a verb + -ing that is used as a noun. Present participles in English also end with -ing, but present participles do not act as nouns. Instead, they act as modifiers or complete progressive verbs.

The infinitive of a verb is its basic form.
The infinitive has two forms:
the TO-infinitive = TO + base
the zero (bare) infinitive = base

Some verbs describe states and are not normally used in a continuous form. State verbs often:

describe emotions or mental states or processes

adore

appreciate (=value)...

Different uses of auxiliary verbs
Auxiliary verbs often emphasise things, show interest, or avoid repetition. If they are used alone, remember they must agree with the tense and person of the main sentence.
To emphasise
Are you hungry?
Yes, I am!
I don't think you want to go
I do want to go, but...

All perfect tenses link two points in time. They show actions before a particular time in the present, past or future.

The Present perfect links actions in the past to the present.

This can happen in a number of ways.