`1.` Compare the expressions and formation of past tense in English with those in Vietnamese. 

- English uses specific verb conjugations to indicate the past tense, often by adding "-ed" to the base form of regular verbs.
 - Vietnamese does not use verb conjugations to indicate tense. Instead, it relies on time indicators and context to convey the past tense.
`2.` Compare the formation of Nouns in English with that in Vietnamese.
  - English nouns can be made plural by adding "-s" or "-es," or through irregular forms.
  - Vietnamese nouns remain the same regardless of number; plurality is indicated by quantifiers or context.
`3.` Compare the position of Adjectives in English with that in Vietnamese.

 - In English, adjectives typically precede the nouns they modify.
 - In Vietnamese, adjectives follow the nouns they describe.
`4.` Compare the expressions of modality in English with those in Vietnamese.  

- English expresses modality through modal verbs (can, could, may, might, must, shall, should, will, would).
 - Vietnamese modality is expressed through modal particles or words that are added to the sentence, without changing the verb form.
`5.` Compare the uses or functions of infinitive in English with their expressions in Vietnamese.

 - In English, the infinitive form is "to" followed by the verb and can be used as a noun, adjective, or adverb.
 - Vietnamese does not have an equivalent to the English infinitive; verbs do not change form and their function in the sentence is indicated by other words or the overall structure.