"To be" and its functions. "To have" and its functions

Contents:

1. 
   “To be” and its functions.
   
2. 
   “To have” and its functions.
   
3. 
   Simple Tenses (Active/Passive).
   
4. 
   Continuous Tenses (Active/Passive).
   
5. 
   Perfect Tenses (Active/Passive)
   
6. 
   Sequence of Tenses.
   
7. 
   Modal Verbs.
   
8. 
   Nouns as Attributes.
   
9. 
   Degrees of Comparison of Adjectives and Adverbs.
   
10. 
    Quantifiers: some / any / no / much / few / little.
    
11. 
    Infinitive. Complex Object. Complex Subject. For + Noun + Infinitive Clause.
    
12. 
    Participle. Nominative Absolute Participle Clause.
    
13. 
    Gerund. Gerund Clause. “Ing” – forms.
    
14. 
    Complex Sentences (Zero “that”- clause).
    
15. 
    Inversion.
    
16. 
    Elliptic Sentences.
    
17. 
    “It”, “that”/ “those”, “one”/ “ones” (“both…and”; “either…or”; “neither…nor”).
    
18. 
    Subjunctive Mood. Conditional Sentences. Modals + Perfect Infinitives.
    

1. “To be” and its functions.
I. Make the following sentences negative and translate them:

1. 
   It is difficult to differentiate between those methods.
   
2. 
   The value of this resistor is constant.
   
3. 
   These electrodes are of the same material.
   
4. 
   That element is a capacitor in the circuit.
   
5. 
   These materials are insulators.
   
6. 
   This invention is of great importance.
   
7. 
   This is a special device to measure the current.
   

II. Ask general questions and give the short answers:

1. 
   The flow of electrons through a conductor is similar to the flow of water.
   
2. 
   The practical unit of current is the ampere.
   
3. 
   The ohm is the practical unit of resistance.
   
4. 
   The resistance of a conductor is proportional to its length.
   
5. 
   Series and parallel circuits are the most important.
   
6. 
   These sources of current are primary batteries.
   
7. 
   The portion of a wave above the zero current is the positive half cycle.
   
8. 
   The period is the time required for one cycle of current.
   
9. 
   Inductance, capacitance and resistance are the circuit constants.
   
10. 
    These examples are illustrations.