1.
Scientists ... some major discoveries in the 18th century.
Correct Answer
B. Made
Explanation
The verb "made" is the past tense form of the verb "make". In the context of the sentence, it indicates that scientists accomplished or achieved some major discoveries in the 18th century. The use of the past tense is appropriate because the 18th century is in the past. The other options are grammatically incorrect or do not match the tense of the sentence.
2.
I ... contacts with a few of my old friends when I moved away.
Correct Answer
B. Lost
Explanation
The correct answer is "lost." This is because the sentence is in the past tense and the verb "lost" is the correct past tense form of the verb "lose." It indicates that the speaker had some contacts with old friends in the past, but they are no longer in touch with them after moving away.
3.
Scientists ...that spider silk can be used in manufacturing bio-materials for medicine.
Correct Answer
C. Have discovered
Explanation
The correct answer is "have discovered." This is because the sentence is referring to a group of scientists, indicating that the subject is plural. Therefore, the plural form of the verb "to discover" should be used, which is "have discovered."
4.
I'm sure I .. that he worked in Baku a few years ago.
Correct Answer
B. Have heard
Explanation
The correct answer is "have heard" because the sentence is in the present perfect tense and "have heard" is the correct past participle form of the verb "hear" in this tense. The speaker is expressing their certainty about a past event (hearing about someone working in Baku) that has a connection to the present.
5.
Tim Burton ... 15 films and his latest film is "Dark Shadows". Have you seen it?
Correct Answer
B. Has directed
Explanation
The correct answer is "has directed" because the sentence is referring to Tim Burton's past actions of directing films. The use of "has" indicates that he has directed 15 films in the past, including his latest film "Dark Shadows".
6.
She ... him when they were working in Japan.
Correct Answer
A. Knew
Explanation
The correct answer is "knew." This is because the sentence is in the past tense, indicating that the action of knowing happened in the past. The verb "knew" is the simple past tense form of "know," which is appropriate for this context. The other options ("has known," "was known," "is known") do not fit the past tense requirement of the sentence.
7.
I ... a member of this forum since January and I like it.
Correct Answer
D. Have been
Explanation
The sentence is in the present perfect tense, which is used to talk about an action that started in the past and is still ongoing in the present. "Have been" is the correct form of the verb to use in this case. It indicates that the person became a member of the forum in January and continues to be a member up until now.
8.
We ... hundreds of letters of support in the last week.
Correct Answer
B. Have received
Explanation
The correct answer is "have received" because the phrase "in the last week" indicates a time period that is still ongoing. The present perfect tense "have received" is used to describe an action that started in the past and is still relevant in the present.
9.
Don't disturb Anna. She ...to sleep.
Correct Answer
A. Has just gone
Explanation
The correct answer is "has just gone". This is because the phrase "has just gone" indicates that Anna recently left and is currently not available. The use of the present perfect tense "has gone" suggests that the action of leaving occurred in the recent past and has a connection to the present moment.
10.
Why ...me before about it? I would have told you.
Correct Answer
C. Didn't you ask
Explanation
The correct answer is "didn't you ask" because the question is referring to a past event or situation in which the person being asked did not inquire or seek information about something. The past tense "didn't" is used to indicate that the person did not ask in the past, while "you ask" is the correct form of the verb to match the subject "you".