Need help with the following questions:

Q1) Mrs Chen ________ for the doctor's clinic already.
1) left 2) has left
3) had left 4) was leaving
Is the answer (1) or (2)?

Q2) John ______ to the library since nine o'clock this morning, he should be back soon.
1) goes 2) went
3) is going 4) has gone
Is the answer (2) or (4)?

Q3) She was very upset ______ the way those boys treated the poor kitten.
1) about 2) at
3) on 4) after
Is the answer (1) or (2)? Or are both answers acceptable?
How about "with" as in "upset with"?

Q1) 2

Q2) 2

Q3) Yes, both 1 and 2 are correct.

You could use "with" in this sentence:
She was very upset with those boys.

None of the answers is correct for 2).

Q2) John has been at the library since nine o'clock this morning; he should be back soon.

or

Q2) John went to the library at nine o'clock this morning; he should be back soon.

For the first question:

To find the correct answer, let's analyze the sentence structure. The sentence "Mrs Chen ________ for the doctor's clinic already" indicates an action that has happened in the past but has a connection to the present.

Option 1, "left," is in the simple past tense, which indicates a completed action in the past without any connection to the present.

Option 2, "has left," is in the present perfect tense, which indicates a completed action in the past that has a connection to the present. This option fits the sentence structure since it implies that Mrs Chen has left in the past, but she is probably still away or on her way back.

Option 3, "had left," is in the past perfect tense, which is used when there are two actions in the past and one happened before the other. However, there is no clear indication of two past actions in the sentence, so this option can be eliminated.

Option 4, "was leaving," is in the past continuous tense and indicates an ongoing action in the past. This option does not fit the sentence structure since it suggests that Mrs Chen was in the process of leaving but did not actually leave.

Therefore, the correct answer for the first question is (2) "has left."

For the second question:

The sentence "John ______ to the library since nine o'clock this morning, he should be back soon" indicates an ongoing action that started in the past and is still happening at the present time.

Option 1, "goes," is in the present tense and does not fit the sentence structure, as it suggests a routine or habitual action rather than an ongoing action.

Option 2, "went," is in the simple past tense, which indicates a completed action in the past without any connection to the present. This option does not fit the sentence structure since it implies that John went to the library in the past but does not provide information about the ongoing action.

Option 3, "is going," is in the present continuous tense, which indicates an ongoing action in the present. This option does not fit the sentence structure since it suggests that John is currently going to the library, rather than already being there since nine o'clock in the morning.

Option 4, "has gone," is in the present perfect tense, which indicates a completed action in the past that has a connection to the present. This option fits the sentence structure as it indicates that John has gone to the library since nine o'clock in the morning and is still there.

Therefore, the correct answer for the second question is (4) "has gone."

For the third question:

The sentence "She was very upset ______ the way those boys treated the poor kitten" indicates the cause or reason for her being upset.

Option 1, "about," is a preposition commonly used to show the cause or reason for feeling a certain way. This option fits the sentence structure since it indicates that she was upset about the way those boys treated the poor kitten.

Option 2, "at," is also a preposition that can be used to express anger or annoyance towards someone or something. This option is also acceptable and fits the sentence structure, implying that she was upset at the way those boys treated the poor kitten.

Option 3, "on," is not commonly used to express the cause or reason for being upset, so this option can be eliminated.

Option 4, "after," is a preposition indicating something that happens later in time, which does not fit the sentence structure since it does not capture the cause or reason for her being upset.

Therefore, both options 1 and 2, "about" and "at," can be considered correct answers for the third question. Additionally, "with" can also be used to indicate the cause or reason for being upset, so it is also an acceptable choice.