1. When does Professor Johnson come to his office, but when he arrives, I speak to him about it? 2. Who will take care

Theme: Simple Present vs Present Continuous

Разъяснение:
1. When does Professor Johnson come to his office, but when he arrives, I speak to him about it?
The correct usage here would be the simple present tense for the first part of the sentence, "When does Professor Johnson come to his office?" This implies a regular or habitual action. However, for the second part, "when he arrives, I speak to him about it," the present continuous tense is more appropriate. This is because it refers to a temporary action happening at the same time as the simple present action.

2. Who will take care of the dog when you go to America?
Here, the future simple tense "will" is used for the main action, "you go to America." The present simple tense "take care" is used for the subordinate action, expressing a general or habitual action. The present continuous tense is not used because it does not fit the context of the sentence.

3. Do you believe you will be working here in a few years" time?
In this sentence, the future simple tense "will" is used for the main action, "you will be working here in a few years" time." The present simple tense "do you believe" is used to express a general or habitual action.

4. The house had been burning for two hours when the firefighters finally arrived.
In this sentence, the past perfect continuous tense "had been burning" is used to show that the house was burning for a continuous period of time. The past simple tense "arrived" is used for the second action, which happened after the first action was completed.

5. She is uncertain if she can find his telephone number in the telephone directory.
Here, the present simple tense "she can find" is used to express a general or habitual action. The present continuous tense "is uncertain" is used to describe her current state of mind.

6. How long has Jerry been studying chemistry when he enters a medical school?
In this sentence, the present perfect continuous tense "has been studying" is used to show the duration of an action that started in the past and is still ongoing. The simple present tense "he enters" is used to express a future action.

7. I cannot meet you this evening since a friend of mine is coming to see me.
The present simple tense "cannot meet" is used to express a general or habitual action. The present continuous tense "is coming" is used to describe a temporary action happening at the same time as the simple present action.

8. What are you reading?
Here, the present continuous tense "are you reading" is used to describe an action happening at the moment of speaking.

Например:
Explain the difference between the simple present and the present continuous tenses in the following sentences:
- "I eat breakfast every day." (Simple Present)
- "I am eating breakfast right now." (Present Continuous)

Совет:
To understand the difference between the simple present and the present continuous tenses, it is important to consider the time frame of the action. The simple present tense is used for general or habitual actions, while the present continuous tense is used for temporary actions happening at the moment of speaking.

Закрепляющее упражнение:
Please rewrite the following sentences, changing the verb tense to the correct one:

1. She usually plays tennis on weekends. (Present Continuous)
2. They have been living in that house for five years. (Simple Present)
3. I"m thinking about going on vacation next month. (Simple Present)
4. He is studying French at the moment. (Simple Present)
5. We have been waiting for the bus for half an hour. (Present Continuous)