Question

I learned English in school but I _ most of it forget/forgotten/have forget/have forgotten

Answer 1

I learned English in school but I have forgotten most of it.

Explanation:

• Have is a verb and can be used in numerous ways in English.
• Sometimes it is used as an auxiliary verb and sometimes as an ordinary verb.
• Have as an ordinary verb shows the ideas like the ownership of things, or a person's traits and relationships.
• It is mostly used in the present tense when the noun is plural or the pronouns are I, you, they and we.

Answer 2

Fill in the blanks:

I learned English in school but I have forgotten most of it.

Explanation:

• The verb is used to define the action of the subject. It can be past, present and future tense.  
• The forgotten is the past participle form of forget.
• The tense used in the sentence is past perfect tense. The construction of the tense is "have + past participle form of the verb".