gmat prep questions

1)
D and E are wrong contruction of -ing participle.Now correct idioms in 'interact with' so we have A and C.C is awkard and so A.

2)
A) correct
B) no subject of 'quickly built'
C) sentence is awkard.clauses are not constructed correctly.
D)Subject is missing
E) clauses are not joined correctly to make complex sentence. Even though and but are redundant.

Q 1:
The "cluster of tribes" contains more than 2 tribes, so you cannot use "between" (which is only used for quantities of 2). That ditches A and D.

For B, C, and E it comes down to an idiom issue--"interacted with," not "interacting among."

This question is sneaky of them, because they know that some test-takers will see a between/among split--yes, "among" is used for quantities of 3 rather than "between" but circumventing the choice altogether is also fine. The idiom takes precedence here.

C

Q 2:

"Even though" is incorrect here because the two clauses connected by that phrase must have a more specific type of relationship between them:

Ex: Even though I hate broccoli, I eat it because it's good for me.

The two clauses must imply a contradiction between them--think of "even though" as the equivalent of the phrase "despite the fact that." Because I hate broccoli, you would think that I don't eat it...but I do!

The fact that Galileo did not invent the telescope does not imply that he could not have quickly made his own later.

"But" is in a similar family of meaning, but has looser restrictions--
-I hate broccoli, but I eat it. (correct, and similar intent to "even though" example above)
-I hate broccoli, but I love carrots (also correct, but there is nothing about hating broccoli that implies I wouldn't love carrots..."but" has wider parameters)


That knocks off C, D, and E.

Notice that B uses the past perfect tense ("had not invented")-- we use the past perfect to show that an event in the past happened *before* another event in the past,. If that meaning is not clearly the intention, then do not use the past perfect. However, if we look closing at the verbs, the actual sequence of events is:

(1) the telescope was made
(2) Galileo built his own

We need the making of the optical instrument to be expressed in the past perfect! So B is out.

Answer is A.

Q 2:

"Even though" is incorrect here because the two clauses connected by that phrase must have a more specific type of relationship between them:

Ex: Even though I hate broccoli, I eat it because it's good for me.

The two clauses must imply a contradiction between them--think of "even though" as the equivalent of the phrase "despite the fact that." Because I hate broccoli, you would think that I don't eat it...but I do!

The fact that Galileo did not invent the telescope does not imply that he could not have quickly made his own later.

"But" is in a similar family of meaning, but has looser restrictions--
-I hate broccoli, but I eat it. (correct, and similar intent to "even though" example above)
-I hate broccoli, but I love carrots (also correct, but there is nothing about hating broccoli that implies I wouldn't love carrots..."but" has wider parameters)


That knocks off C, D, and E.

Notice that B uses the past perfect tense ("had not invented")-- we use the past perfect to show that an event in the past happened *before* another event in the past,. If that meaning is not clearly the intention, then do not use the past perfect. However, if we look closing at the verbs, the actual sequence of events is:

(1) the telescope was made
(2) Galileo built his own

We need the making of the optical instrument to be expressed in the past perfect! So B is out.

Answer is A.

Q 2:

"Even though" is incorrect here because the two clauses connected by that phrase must have a more specific type of relationship between them:

Ex: Even though I hate broccoli, I eat it because it's good for me.

The two clauses must imply a contradiction between them--think of "even though" as the equivalent of the phrase "despite the fact that." Because I hate broccoli, you would think that I don't eat it...but I do!

The fact that Galileo did not invent the telescope does not imply that he could not have quickly made his own later.

"But" is in a similar family of meaning, but has looser restrictions--
-I hate broccoli, but I eat it. (correct, and similar intent to "even though" example above)
-I hate broccoli, but I love carrots (also correct, but there is nothing about hating broccoli that implies I wouldn't love carrots..."but" has wider parameters)


That knocks off C, D, and E.

Notice that B uses the past perfect tense ("had not invented")-- we use the past perfect to show that an event in the past happened *before* another event in the past,. If that meaning is not clearly the intention, then do not use the past perfect. However, if we look closing at the verbs, the actual sequence of events is:

(1) the telescope was made
(2) Galileo built his own

We need the making of the optical instrument to be expressed in the past perfect! So B is out.

Answer is A.

Q 2:

"Even though" is incorrect here because the two clauses connected by that phrase must have a more specific type of relationship between them:

Ex: Even though I hate broccoli, I eat it because it's good for me.

The two clauses must imply a contradiction between them--think of "even though" as the equivalent of the phrase "despite the fact that." Because I hate broccoli, you would think that I don't eat it...but I do!

The fact that Galileo did not invent the telescope does not imply that he could not have quickly made his own later.

"But" is in a similar family of meaning, but has looser restrictions--
-I hate broccoli, but I eat it. (correct, and similar intent to "even though" example above)
-I hate broccoli, but I love carrots (also correct, but there is nothing about hating broccoli that implies I wouldn't love carrots..."but" has wider parameters)


That knocks off C, D, and E.

Notice that B uses the past perfect tense ("had not invented")-- we use the past perfect to show that an event in the past happened *before* another event in the past,. If that meaning is not clearly the intention, then do not use the past perfect. However, if we look closing at the verbs, the actual sequence of events is:

(1) the telescope was made
(2) Galileo built his own

We need the making of the optical instrument to be expressed in the past perfect! So B is out.

Answer is A.